It must be tough being in a relationship with a famous guy if all the girls are chasing him. I'm not famous, and I won't pretend I have any idea where your guy's head is at. But here's what I suggest you do.
I think you should talk to your guy and tell him how you feel. Ask him what he wants from you, and encourage him to be honest with you so you can both figure out if you're likely to have a future together.
I know lots of famous guys have long-lasting relationships with girlfriends who become wives. But at least as many (probably more) end up ditching their partners to take advantage of all the women chasing them.
Perhaps your boyfriend wants you to be by his side all the time (or nearly all the time). In which case, are you prepared to do that?
Or maybe he wants you to stay home and raise children while he travels. You'd have to ask yourself if you'd be happy doing that.
I think in your position, the big challenge will be trust. Maybe you trust him, but don't trust the women throwing themselves at him. You need to decide whether or not you have enough confidence in your guy to remain loyal to you.
If you don't, perhaps you should consider wishing him well and walking away. But if you're confident the two of you can work it out, then give it a go. I do think one thing you should ask him is to promise he will phone you and tell you if ever he meets another woman he wants to sleep with. So you both know your relationship is over before he comes home and lies to you.