My bestfriend and my x boyfriend

I went out with this guy named Jonathan for about a month. I broke up with him but only because I knew he was going to break up with me soon. I still like him and I know he still has feelings for me. The only problem is he's " not mature enough for any girlfriend right now" and I can understand because he is immature a little. But we cant be together for a while maybe even a year or two. Well I have a Bestfriend her name is Veronica and she can have like any guy she wants. Well of course she likes Jonathan. Even though shes with his best friend. I think she just wants him because she knows I want him. She might be my best-friend but shes admited to doing that before to another friend of hers. ( who I dont know ). I just cant handle hearing her talk about the guy I like and was with all day. What Should I Do?!?!

You don't have any control over what your boyfriend does, or who she likes. But why would you keep a boyfriend who disregards your feelings? [I think she just wants him because she knows I want him.] Is that boyfriend behavior?

Also, you stated that the guy is just immature right now and not ready for a steady. If this is true, then let him 'go' with whomever he wants--it won't last.

Just watch him from afar until he ripens and matures.