The common wisdom is that it doesn't matter which spouse files first.  In your case, without any custody/parenting issues to blow issues out of proportion, that may be true.  No one can predict in advance.  However, the fact is she has raised the level of conflict by involving the police.

I often write that it was so astounding how my ex could be such an aggressive purported "victim".  In our case, we had a young preschooler and the divorce was all about custody/parenting.  The allegations and vitriol were horrible and endless.  The divorce process took a couple years.  So for me it was different... I felt better by knowing that I was the Plaintiff and my disordered but undiagnosed ex was the Defendant.

If you haven't started interviewing experienced attorneys, then now is the time to do so.  You need to know where you stand on a multitude of legal matters.  Laws and procedures vary from one state to another, even from one county to another.  It's far better to know where you stand rather than guess.

Now, there is a real difference between repairing a relationship (where you share information tom rebuild trust) and ending a relationship (where you restrict what you choose to share so that such information cannot be used to sabotage you).  Your lawyer would agree with that wise stance.

You may feel you need to be overly "fair" and must share with your soon-to-be ex (stbEx).  While that sense of fairness is likely strong with you, as it is with many of us here, beware.  You already know that your desire for fairness won't be reciprocated by your spouse.  As the old saying goes, "Loose lips sink ships."  Whenever in doubt whether to share any new information, consult your lawyer, therapist or even peer support here.

That was your reality check.  Quite sad but not unexpected.

Overall, I've come to a conclusion which so many have come to as well... We can spend so much time and effort in our efforts to turn around our close relationship with a person who too often sabotages close relationships when they put too much weight to emotional feelings and resist facts.

They too often simply won't or can't get past the baggage of the relationship to truly listen to us.  But... they might be receptive to a therapist who is both experienced and yet does not have a close emotional relationship with them.  If therapy starts, continues and is meaningfully applied in life, perceptions and thinking... progress is possible.  If not, then... it may be time to cut your losses.

Thank you all for the advice.
I have made a list of the bad memories and have left plenty of room to add more as they come to mind. It's honestly scary. I can't believe I have stuck around as long as I have!
When it comes to shared assets, debts, etc. We really don't have any. We don't own anything together and all of our finances have been separate from the start. We don't have a shared bank account and all of our credit cards are in one name only. Given the nature of our relationship, I have been cautious from the start.
As for getting my stuff back. Fortunately, a lot of what is important to me is in a storage unit that only I have access to. She has a lot of things in there as well. There isn't much at the place she is currently living, but it is stuff I would like to have back. My current plan of action is to have her put it somewhere I can get to it without having to go inside and then pick it up on a day I know she won't be home. 
She also took my dog and is refusing to give her back. A number of years ago, she bought the dog for me as a birthday gift. Before I left, she said because she paid for the dog it is now hers. Funny thing about this is that on numerous occasions, at times when we weren't in the same place, she has thrown a fit about the fact that she has had to take care of "my dog" and has threatened to take her and drop her off somewhere. Suddenly, it has become her dog and she is refusing to giver her back to me.
I agree that it would be in my best interest to get ahead of the game and not allow her to file first. Knowing her, I have a hard time believing she would take the time or make the effort at this point, but I know I shouldn't count on that.
It's been about 5 days of no contact at this point. I still have my ups and downs, but feel that I am in a better place than I have been in the past when going through this. The silence on her end is making me a bit nervous. I keep expecting her to reach out but she hasn't. I think a lot of it has to do with the fact that this is a really busy time of year for her with work so she really doesn't have much free time. I am concerned that when reality sets in, things could get ugly. This has been the pattern in the past. I am keeping my fingers crossed!
 

Well it didn't go well. I tried with the advice. She jumped in and wouldn't back down on everything being my fault. She said she needed to get off the phone. It doesn't look good. And frankly, this showed me how impossible the relationship would be.

A lot of useful stuff here. Thank you.
But to be clear I am not sending her money and she has not asked. We have periodically shared financial gifts with all of our kids (my husband has older from his late wife) without being  asked. Mostly directed to college funds.

This daughter has always supported herself and not asked.

My inquiry was wanting to be prepared for a possible request when she perhaps ‘hits bottom’ or has some sort of crisis. .
Again, very helpful.  Thank you.

This is great. I need to keep this handy until I learn to do it naturally.

I've been listening to an audio book on strengthening our relationship and one of the suggestions it has is giving my SO a compliment a day for a week. I know for a fact that Words of Affirmation are her love language but this is something that doesn't come naturally to me. I can be encouraging, show support, and I tell her multiple times a day that I love her. The times I try to go beyond that she'll hit me with a "tell me something else" and keep pushing me until I freeze up and it usually ends with both of us upset because, as she says, "you never say anything nice about me" and I end up feeling like I'm not good enough that I can't give her what she craves the most. Alternately, she'll say "you don't have to say that", which stings just as much.

Anyone have any tools to get through this kind of situation? All I've got is to not say much and I don't feel like that is good either.

I've gone through this myself. I've pushed a few times for my wife to see someone but never by telling her that she needs to be the one to go. I've suggested going for couples counseling and framed it as my needing help. That, at least, went over well enough, even if I didn't actually get her entirely on board. I have on 2 separate occasions started seeing a councilor on my own when I have become overwhelmed. Through seeing improvements in myself she has at times mentioned that she was going to look into seeing someone herself but has not yet. When she brings it up I'll usually say something encouraging without pushing. Something like "we could all use help sometimes" or "everyone should see a therapist from time to time."

Don't be afraid to seek help yourself. The times I've gone have been incredibly helpful.

All you can do at this point is try.  Maybe it works out, maybe not.  But as your going through this process and focusing on "I", you're actually making a shift in the relationship without realizing it.  You're starting to prioritize your feelings over hers, your needs over her wants, your mental health over her demands, etc.  And while that might sound counter-productive, it's the only thing that has a chance of balancing out the relationship and actually giving it a real chance.

Just remember, it's okay to validate her feelings.  If she's sad, you get what that feels like, so you can comfort someone that's sad.  However, you don't validate her facts when it's not reality.  Just stick to feelings and you'll have a lot less resistance.

Thank you both so very much.  This is incredibly helpful as I prepare for tonight. You saved me from walking in with the wrong list, even though my intentions are the same. I've tweaked it all with your solid advice, Pook075. ForeverDad, you're right she has had many failed relationships, with people who were all "mean" or stopped loving her.

I'm at a point where I feel working together in therapy is the only way, so I agree that framing it as the therapist being there only to guide us as we work through conflict and build trust is the right answer. I truly don't care about winning, so that's easy to say. And I do care about her, so that's easy as well.