Definition: Given a real-life anecdote of a complex ethical situation, generate a suitable title that describes the main event/root cause of the situation. Imagine that the given text is a social media post, and you have to write the title of the post, so the users can decide to read the main text or not.
Input: Throw away account since I have friends who know my main account.

So just a little back story here, my girlfriend works in the medical field and is very successful, and she has no money issues whatsoever, so the price isn't what's bothering me.

My gf and her ex dated over 10 years ago and stayed friends after breaking up. They dated in their early 20s and now we're all in our early-mid 30s. I've never had a problem with him hanging around, and I've never had any reason to think they were still seeing each other. He comes over all the time and he's a chill dude, we get along fine. 

Recently he'd been having car issues, and he doesn't make enough to be able to fix them all right away, and buying a new car was completely out of his budget. This is when my gf told me she was going to buy him a new Tesla model 3.

She's never been one to spoil him with gifts or give him charity at all, sometimes he'll stay for dinner but that's really it. So this was a big shock to me. I probably had a bad initial reaction when she told me because the first convo ended in a big fight. I asked her why she felt the need to do this for him, if she was still in love with him, had they been fucking, and a lot of things I really shouldnt have said. She just told me that what she did with her money was none of my business, and it was "the least she could do" for all the support her ex had given her over the years.

I think this is completely ridiculous. I get that it's her money, but this just reeks of a giant red flag. Spending $50k on an ex just because he's having car trouble is insane to me. She told me that I was being unreasonable and if I had such a huge issue with this, then we'd have to "reconsider things."

She already bought him the car and now is waiting on the delivery, and she and I haven't spoken in about a week. I've talked to some friends about this and its about 50-50 on whether I'm in the wrong here.

So reddit, AITA?

being pissed that my gf just bought her ex a new car