willtimeheal, it sounds like you've done a lot of healing and have been enjoying life, which is awesome!

Don't think of days like this as a setback at all.
Her birthday coming up certainly could be a trigger for these feelings. It makes sense that she would be on your mind more.
Is it normal to get in a rut like this?
I say it's not a rut, it can just take longer to detach than we really wanted.
I agree... .remember, the healing process is just that, a process. It takes a while, and it's not linear. It's normal to sometimes "cycle back" -- it doesn't mean we've lost our progress at all.
And then one day the dreaming stopped and I haven't dreamt about her in a long time; it takes what it takes.
So hang in there, maybe it's not a rut, it's just a process that is taking longer than you thought it would. Keep moving forward, you got this.

I know I am looking for validation that I mattered to her.
Our feelings are trying to tell us important things about ourselves.
Why is this important to you? Why do you need validation that you mattered to her?