PLEASE HELP? I"M SUFFERING! What should I do ?!?!?!?

[loveyoustill]

My boyfriend and I used to love each other very very much. But these days I realize that he is acting very cold to me, and he acting a little intimate with the other girl (who likes him). I know that he's being intimate to this girl because they need to practice dancing together for their performance. They seem have some of very intimate act during their performance so I'm VERY worry about that. He, once, never talk a lot to this girl. Now he's very open, he talks and smiles with this girl A LOT, and often look at her. I think he's losing interest in me and started liking this girl.
NOW, the really BIG problem is that this girl likes him. Today after work they need to go to practice dancing together at a private place so I'm EXTREMELY worry now! She likes him so OF COURSE she gotta do something to flirt him at that private place and I realize that he's also a little like her too so what can I do now? (I can't go to that place for some reasons please don't ask about that reason).
And ALSO in the next Monday after performance with that girl at the morning, I'm going to meet him at the evening. What should I do for him to forget her? What should I do if he's being cold to me? What should I do if they're being so intimate? PLEASE HELP! I'm very suffer right now.
PS: I love him VERY MUCH so don't ever advice to break up.
Guys, any advice.
Thanks for reading.

[Bonfire]

You just have to have faith that his love for you is stronger than his interest in her. If you try anything it can make matters worst. Desperation is unattractive. When their show is over and just let him know that it will make you uncomfortable if he continues to spent time with her if there is no need.

[thundersw]

You can try to look prettier/more attractive to your boyfriend then the other girl. I'm sure his eyes will get back to you again.

[simonk]

True, try your best, he may notice. It may be just a temporaray mishap and he doesn't realize he's hurting you.

Talk to him if it gets out of hand, mention you're in pain, if he cares he'll stop it.

[findingaway]

Oh, I really feel for you. That really is an awful situation.

If I were you I would face up to him - take him on a long walk or somewhere else he is comfortable and won't feel crowded, cornered or pounced on and talk openly that you feel the relationship has lost it's romance. Ask him how he feels.

Have you thought about doing this?