I enjoy it when my girlfriend goes on a girls night out scantily clad and dancing on a stripper pole for a bunch of strange men to oogle.
I don't think it is out of line for bitsoda to feel uneasy or unhappy with her behavior, especially since it does not seem like their relationship is as open or alternative as some other peoples' partnerships. If they had met in a strip club, or participate in S&M, or do some kinky stuff that couples do, then such behavior may be implicitly okay. However, my impression of Bitsoda and his gf is that they have a slightly more conservative relationship.
Bitsoda, if you don't like this behavior, then say so. No, I don't think you should leave her, and yes, I think you guys should really talk about it. In addition, I would be wary of her co-worker. I had a really good friend who became a girlfriend, but due to her parents' divorce wanted to sleep around. She would get really really drunk and bounce between me and another guy. She would also go to strip joints with her friends' on 'adventures' and stay out all night. I was really uncomfortable with that behavior, and ended up leaving her so that she could be with the other guy.
I'm a guy, so I'm out of my lane here, but I got the impression from some girls that they wanted to strip. I think there's empowerment in flexing ones' sexuality. However, that your girlfriend then wanted to commit suicide (really?) rings some alarm bells in my head.
Anyway, hope it all works out. Good relationships are a rare thing and worth holding on to, even in rocky times.