Welcome, passin thru!

I'd like to join
Mutt in welcoming you to the discussion forums. From what you've written, you and I (and many others here) have a lot in common. First, we have the "light bulb" moment when we first find out about BPD - and it explains so much. Then, we reach out to others for support, as you have. So, welcome, you're in the right place.
Thank you for sharing with us what you have thus far:
I have questions surrounding interaction with my spouse:
Do I talk to her about her condition? or avoid it all together?
If your wife does not yet know that she may suffer from BPD, I agree with
Mutt and
isilme, it is not best practice to "armchair diagnose" our spouses by suggesting they have a stigmatizing disorder such as BPD. Since you are now undergoing a termed one-year separation, the idea here is to separate with each individual working on his/her "stuff." You may be more successful in getting her into therapy by making it a condition for reconciliation.
How do you know when it's the right time to discuss getting help?
In my opinion, both of you would benefit from individual counseling. So, the right time to be talking about getting help (for both of you) would be
now. If your wife starts talking to you about
her own conclusion that she may have BPD, then it's fair game regarding that particular issue.
I would rather see our relationship healed than end... .but I have decided not to get back together if she does not get help. When do I tell her this?
I understand you're not wanting to see this relationship end, and it's noble for you to give your marriage any shot of success. Most likely, in addition to marriage counseling, both of you will need
individual counseling in order for this to be possible. If at any point during your separation your wife wants to reconcile, again, you can suggest that she gets individual therapy a firm condition for reconciliation. If she's not interested in individual therapy, then you'll know your answer and can, therefore, proceed according to your values.
I'm in no rush to make changes to our relationship only myself.
Well, the only thing/entity in this relationship that you can actually change is YOU. The more you know how to do that, the better.
We can help.I know you are here by way of sorrow, but I just want you to know that you are among peers, friend. Unfortunately, there are legions of us! I'm so sorry you are experiencing this. However, I think you'll find a lot of parallels here - lots of members (including me) have similar stories. You will see from reading the posts here that you are far from alone. Please let us know how best to support you. Keep us posted on how things are going for you. Hang in there.
Keep writing, keep processing, keep learning.
-Speck