Probably insecurity, or he is telling you that he chose you and only you out of those girls...
is his kissing other girls or other guys?
All girls are intrested in having a boyfriend, its natural.
Yes, some girls do that, but not all girls do. They do it when they feel insecure about the relationship. Don't forget, if she lies about her ex, she will lie about you. And, most likely lie to you. A good thing to know about before you plunge in to a relationship.
Who gives a cheese what other girls think of your boyfriend the other girls are just idiots if there's noting wrong with him but if there telling you stuff that can't be ignored then INVESTIGATE
Find someone that is more interested in you.
Either the boyfriend makes a move or they say they "I love you." to the girl.
You can't prevent other people from being attracted to or even hitting on your boyfriend. Attempting to confront them will make you appear insecure, and in some cases will only fuel the flirting/hitting on, as the individual might believe they're getting to you and your relationship. Likewise, you have no control over how your boyfriend responds to their behavior. He is mature enough to be able to deal with these girls himself, either by ignoring them or telling them outright he is not interested (if they come onto him). He may not even be aware that these girls like him, while you are too aware of it. However, if he seems to enjoy their attention, spends time with these girls and flirts back, even after you've told him how you feel, you need to decide if you want to be with someone whose need for attention is more important than your feelings.
Although the girl says she is not interested, she probably still feels flattered that you like her and wants to keep your attention because she is insecure.
It means she has a boyfriend, or is simply not interested in you.
MY opinion of why they get boyfriends is because they dont put themselves out there like the non insecure girls do.
sometime yes, because there are many girls (teenagers particularly) that only have a boyfriend because they feel they have to, or just like to know they have someone by their side. they could very well be interested in someone else, but just hanging onto their boyfriend for now. personally, i would never be like that, but there are many who are.
Don't feel bad, I'm 14 and I haven't kissed anybody