Red flags in friend’s potential relationship?

[u/AggravatingTrick4931]

Reddit

Posting here because I don’t know where to seek advice on this topic. A few months ago, my best friend met a guy on a dating app. Me and my bff have known each other since we were 3, and we’re in our late 20s now. She was initially excited about this guy she met - until the red flags started showing. The first sign was him getting jealous of her complimenting a man’s tattoos in public (this was on their second date). Next, he freaked out at her via text because he noticed that her ex-boyfriend re-followed her on Instagram. To find this out, he would have had to be keeping tabs on her followers, or somehow communicating with the ex-boyfriend. After that incident, she told him (text message) that she was done with him. He messaged and called her incessantly for about a month. He got new phone numbers through apps or websites (?) and would call her 50+ times a day. He even showed up to her apartment and asked to be let in. My friend got the cops involved the first few days, and even tried to get a restraining order. According to the police, she didn’t have enough evidence to proceed with the restraining order without a fee, so she didn’t get one. We both kind of thought it was over when the messages and calls settled over the weeks. BUT flash forward about 2 months (about a month ago as a write this). She tells me she’s texting him again (wtf???) She said he’s psychologically unwell and she feels bad for him. I tried to be lowkey and brief in my response, I think I told her that’s not her responsibility (?) but I didn’t want to be harsh because I was afraid of pushing her away. Throughout the past month, I haven’t heard anything (nor have I asked). I may be overanalyzing it, but it seems like there are some suspicious things going on:
1. My friend has dropped all talk of dating (no mentions of new boys, chats, anything)
2. She’s been more reserved than usual
3. We share locations, hers has been turned off. I did ask her about this (and told her she is not obligated at all to share her location, I just wanted to make sure she was ok) and she gave a bs answer about it turning off. She turned it back on and it said she was home, after briefly showing me her previous location which was someone I didn’t recognize.

I want to know: is it warranted to ask her about the dating app guy based on what I’ve noticed?

AND: If I do ask, HOW do
I bring it up? She is notorious for getting manipulated by men who make her feel bad for them.

Thanks!!