I'm sorry you had another bad day.
You wrote...
If it comes to letting it all go, I will do it. If I continue to feel like I have, it won't be worth it. I'm going to let things be for at least another week maybe more, while I collect all my thoughts, and write them down. Then after we both feel a little more stable have another conversation.
Well, you are about 3 days in. So almost half way through the week. You could make it to the end of the week and then talk to her. If she's still carrying on where your feelings are ignored while she does whatever she wants and you keep feeling stepped on all over and in pain? Heart broken?
Then you have to get firm.
She has been having a really hard time as well. She soberly told me that her heart and her head were all messed up.
I'm begging to think there are some a actual metal health issues going on now. Some of the stuff she just said to me was totally off the wall.
Maybe you say something like "I love you. But I do not love THIS. And not even for you will I stay in something that hurts me. I need these off putting behaviors need to stop: (list them). Are you willing to stop doing that?
I need this behavior to start -- I need to see that you make a doc appointment for yourself for a check up to show that you are trying to work on this head/heart messed up thing. Are you willing to do that?
Otherwise, we need to part ways so you can do what you want and I can be free of misery."
Speak plain and lay all your cards on the table. Because it sounds like either she works on herself so she's not dinging you so you can be free of misery. Or you walk away so you can be free of misery.
You
staying while she does off putting behavior? Keeps you in misery. Just more of same.
It is possible she was a great companion into sobriety but now once here... not so much. She's simple traded one addiction for another (phone addiction thing) and now this poor treatment of you.
I'm very sorry you deal in this.

Her ignoring your feelings and walking all over you while you watch her LIE to the online people that she's single... That's not great sounding. It's hard to admire or respect someone who chooses to behave toward people that way.
Galagirl