Jealous of girlfriend being chatted up.

Hi. I feel really uncomfortable. I was at a party with my girlfriend and there was guy sat near us. He started talking to my girlfriend and I noticed how involved she was when talking with him, laughing at the things he said. I find it hard to make decent conversation and I wished she was more responsive with me.
He said he was an idiot, and she was like no, no you're not. He invited her out to a night out with his friends, she was really excited about it. I felt really insecure, that I had to 'man up' and try and impress her back but my conversational skills aren't as good. I felt really jealous and humiliated that she was being chatted up in front of me.

We've only been out 8 times, and we've gone the whole way. I've been cheated on before with a different girl.
I am in such a lose-lose situation. If I bring it up and say I was uncomfortable with this, she will think I'm jealous over something she may find trivial. I will give her the power. But if I let stuff like this happen, then I could get walked over and cement a beta-type personality

i have seen that often where before a couple becomes a couple the female talks and is responsive to the guy. and she is very interested in the guy. however when they get in the relationship you see the girl do that for other guys and not so much to the one she is in a relationship with. like she has to gain their acceptance almost. never understood that.

well it is good you only went out together 8 times. your attachment to her is not very deep. so i would think you should let her know what you expect out of the relationship so you both are on the same page. if she doesn't see eye to eye i don't think she's worth investing time in. and you won't have to suffer in the long run.

I used to suffer from some SEVERE jealousy then I read a thread that said "There are a number of ways to demonstrate confidence:
1. body language - take up more space.
2. Your focus should be selfish (don't be a jerk). What I mean is you don't need anyone's approval because you know 100% that you're the prize.
3. Never be emotional, needy, or jealous. Don't ever think of possessing your girl, she'll resent it. Think of how beautiful she is and you are now seeking the truth of whether she is good enough for you. She might not be - you need to consider this, you're the prize, remember; you're hot farking property.
4. Don't be a jerk. Internalize this information. Act like your natural confident self.
5. Have other stuff to do besides seeing her all the time. Make her work for you a little. Again don't be a jerk about it, but have other interest besides the girl. This is important.
6. Be a man. A real man doesn't act like a pussy. He let's his masculinity drive him.
7. Read up on confidence. "

My point is yes you should be more talkative with the girl when the guy was talking to her but instead of asking about the guy say something funny like "That guy at the party was a awesome, I gonna steal him" or something playful like that. Don't overboard homo or anything though just funny and then just change the topic to something else. Also next time try to own the conversation by talking to the guy if it happens again and then say a joke when she laughs Kino escalate and this will let others know she's with you.