<human>: Can you condense the text into three sentences or less?

Background: I have not dated in a verrrry long time-and even to the point where my first bf didn't even really count because it was 2 months in sophomore year of high school. But even still, I feel like this is the first year that I've actually felt ready to date because I've lost weight and gained self-confidence in myself. 

Anyways, my bf and I met at a bar- he sort of invited himself to my group of friends as we were playing a drinking game and we flirted all night because I really liked his sense of humor. We've been having a lot of fun getting to know each other and fooling around and stuff but as I've been getting to know his past relationships, I feel more insecure because he's had much more experience than I do and he's been with more girls. 

What also hasn't helped my insecurity is that yesterday as we were at a checkout line at the grocery store, the cashier hit on him right in front of me! (As if I wasn't good enough for him) 

He's said before that I'm "way hotter" than him and that people look at us like "what is she doing with him?" but now I think he's saying that because the reverse is true.

I'm really trying not to let this get to me. I've seen my friend's relationships crumble because of lack of trust, communication, jealousy, insecurity, all that good stuff and I don't want that to happen to me. I just feel like I was much more confident about myself in the beginning and now I feel unsure and I'm over-thinking everything.
<bot>: I feel like I'm getting more insecure as my relationship continues and I need advice in maintaining my self-confidence and trust in my bf.