<human>: I've been with my bf for two years (m/26, f/22). It's my first 'real' relationship, his second. As such, I am unsure about how to deal with his ex. They broke up because of value differences, but still remain close friends in the same social groups. I've met her a few times and we've hung out, and she is a flirty, touchy-feely person that I am not comfortable having around my bf. I don't know what to do or how to proceed... I spoke with him about it and he kind of blew it off as not a big deal because they are 'just friends'. My bf doesn't like to make people mad, so I don't trust him to say anything to her if she starts to be inappropriate with him until it's too late. 

Thoughts? Also, if anyone has any other advice about ex-SOs, I'd be grateful! I don't like to cause drama but this is really a thorn in my side and I can't seem to get it out of my head. :/

Condense the text into a few key points
<bot>: I don't know how to handle bf's friendly relationship with ex, and I have cause to be nervous because of her past behavior.