Rich, You cannot just wait for her to split from him, pretending that you are willing to accept just friendship.
She knows how you feel.
She has a boyfriend.
She has made her choice.
Maybe, somewhere down the line, you will have a relationship with her again ~ it could be friendship or it could be romance. For now, though, she has a boyfriend, and you have to accept that she will spend a lot of time with him.
If you want to be friends, then just be friendly. Smile. Say hello. But do not expect anything more.
Before I met my husband, I was friendly with one of the local lads. I spent quite a lot of time with him. We went to the youth club together, went for walks, etc, etc. My female friends didn't really like him hanging around, but I got on well with him. He asked me out several times ~ so I know how he felt ~ but I was only willing to be friends & he knew that.
When I started going out with the boyfriend-who-became-my-husband he wondered if there might have been something more between me and this boy, but there never was and there never would be.
I still regarded him as a friend and was friendly when I bumped into him. I wouldn't have gone to the cinema with him ~ not while I was dating someone else.
You might be in a similar position to him, here.
Don't give up hope ~ but don't just wait for them to split up.
Go out and enjoy yourself with your other friends ~ or find a new hobby and make new friends.
Good luck
