As long as you are ok with it. I would suggest you support him.
Often it is a very hard for a person to deal with their sexual difference by themselves. So, try and help him through this time of transition by letting him know that his different sexuality doesn't change who he is as a person or the reason you are with him. I know what I'm talking about here my friend recently admitted to me he was gay.
Try and get him to talk about it, his experiences, the way he feels about it and so on.
It may not seem like much to you, but just them knowing that someone who they care about is ok with who they are as a person can often be a big help for these situations.
EDIT: Additions.
Quote: from Anonymous at 6:57 pm on Dec. 27, 2006
i mean im ok with it...but still...he has this REALLY close guy friend who is always by his house n stuff 
That's is good to hear that you are ok with it.
If he has a guy friend that you think is potentially causing something for him. I suggest you talk to him about it. One hopes he will be truthful and tell you what is really going on. Know that in all relationships communication is key, and that telling how you feel, as well as supporting him through this will help. But really if you have any suspiscion over his guy friend just talk to him about it, and find out what is really going on.
Alot of people think my friend and I are gay and together, just because we spend alot of time together, however we are not (well he is, but that's beside the point.) So they could be very well in the same situation as my friend and I...
Post edited at 7:07 pm on Dec. 27, 2006 by Rastafarian
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Danse Macabre.