Why is my BPD ex suddenly acting so impulsively?

[bpdposter?]

Me and my Borderline ex have been apart for over a year now. She split me black and cut off all contact with me after a month of dating, and then about 3 months ago (after 9 of ignoring me) she contacted me and begged me to come over in the middle of the night- apparently she had tried to kill herself about 2 weeks before that. She wanted to have sex with me but after some making out we fought and she sent me home. She was hospitalized the next day, and we agreed to just be friends (finally).

She was in a really bad place during the 3 months we were on good terms. She avoided phone calls and texts and only hung out with all of our mutual friends every few weeks. She would text or call me if she was feeling really down and I became her confidant, even though I made it clear we were just friends.

Anyway, about a week ago her mood improved- she was communicating with people, laughing, and she seemed like her old self. It was also on this day that I started to complain about how she was treating me (we had fought a week before this about a couple of things- the fact that she would avoid me all the time and the fact that she told me she wanted to kill herself and then proceeded to ignore me all day) and after a I made a few sarcastic comments and refused to come hangout that night, she started ignoring me. After some prodding she pretty much told me she didn't want to ever talk to me again.

Now it seems like her newly improved spirits were merely the beginning of a huge mood swing- our mutual friends expressed discomfort with her mania and odd behavior. Her amphetamine abuse got much, much worse, she got an odd tattoo (homemade) and started sleeping with two different guys. Is there a reason this is all happening after she devalued me again, or is it a coincidence? She's been unusually public about her activities (tweeting sexual things and videos of her shirtless in bed with a guy). Is she trying to make me jealous with her public sexual affairs? thanks for reading, I'm very worried and confused.

What do I do if I'm the cause or reason for her acting out?

[mango_flower]

I'm no expert but this may or may not be BPD related.  Could be something else entirely - bipolar disorder or a result of drug use.

The main thing you can do is just to stay clear.  Difficult I know.  You are NOT the cause of this, she definitely has other stuff going on x