If your getting the "I have a BF" line upon the approach a lot, its more to do with you than rather or not she actually has a BF. It's because you're giving off a bad vibe and can be fixed by fixing your fundamentals. Dress well and have your looks maxed out. Have good posture, relaxed body language, strong eye contact, ad a deep unwavering voice.
If you have been talking with a girl and you find out she has a BF you have one option: Be awesome.
BF destroyers don't work. If a chick actually likes or even loves her guy, and isn't open to cheating, there is no sequence of words you can utter that will make her want to forget about her BF. BF destroyers are marketing gimmicks.
If you want a girl who has a BF.... be better than her BF.
Hope that helps
