My boyfriend figured out that he is bisexual

Just for clarification, I 100% support my boyfriend as I myself am bisexual as well.
So, yesterday me, my boyfriend, and a group of friends were playing truth or dare and our friend, I'll call him T. for anonymity's sake, was dared to kiss my boyfriend (T. is gay). They went through with it and my boyfriend sort of shook if off and was visibly a little weirded out by it, he had never kissed a boy and only he and I had ever kissed. So after it was done and we were all getting ready to go home from the party, I talked to him about it and he told me that he tried to imagine that it was me kissing him. Then I asked him about how it made him feel, since I was curious, and he confessed to me that it made all of his feelings from when he was in middle school and had a "gay phase" come back to him in a rush. He then said that he was bisexual and explained that he had been confused about his sexuality for awhile but that the kiss with T. finally confirmed those mixed feelings he had. He said that he obviously has a leaning towards girls, since we're together and our relationship is going great, but there is that part of him attracted to guys.
We haven't really had an in-depth conversation about it yet, which I want to because I want to understand where he's coming from and help him grow and flourish as a person. My only concern is that this one kiss with someone else could spark all these feelings, and what that means for our relationship, if anything at all. Is there anything that I can do to help my boyfriend come to terms with these new feelings, or should I just not worry about it and let him figure it out himself? Am I wrong in being worried about his newfound feelings, just because they were sparked by a kiss with another person?
Any help would be amazing. Thank you so much!

 

Update: We had a talk about things yesterday, it was difficult because he wasn't being honest with me at first. After a few hours of discussion we decided it was best to take a break so that he can figure himself out in his own time without me being a distraction or a roadblock. I'm very depressed over it right now but I'll probably be okay with time. I hope I did the right thing.

 

I shared this forum with him as a resource, he is the user S4turn. Maybe you could help him out, or direct others that you might know, on the threads he made? He probably has lots of questions to ask from people who are more experienced than either him or I are.
Thank you for the advice and help!

 

Hello, just an update!
We had a pretty long talk over text and phone call, and we decided that it was best for both of us to stay together and work things out as a couple rather than take a break and just act as friends.
He'll probably update you all soon as well about it, but to summarize, he thinks those feelings towards T. are just temporary and derived from the "new" feelings he has for the same-sex and henceforth his hormonal urges from the latter.
We've decided that going back into a relationship with each other it will be based off of trust, understanding, honesty, and support.
So, this begs the question, what can he do to explore his sexuality while being in a committed, nonsexual relationship with a girl?
What can I do, as his girlfriend, to support him through this all, in anyway?
He did make a thread about this, so should I make a thread to try to reach out to more people?
Thank you for all your help!

 

Update:
All of that was for nothing, all my support was for nothing as he decided to go behind my back, lie to T. about us being together, schedule a time and place to meet up so that he could kiss him again, all while lying to me about trust and honesty!!!!
YAY!!!

I broke up with him.

 

Thank you for the kind words and support! I'm trying my best to move on and get over him, right now I keep fluctuating between being mad and sad, but overall I know I did the right thing. I just wish that instead of just being honest and letting us both end the relationship mutually and without the extra hurt and sadness, he had to attempt to take the easy way out and stay with me while also trying to get what he wanted from T. Luckily T. let me know what was going on before he could actually cheat on me, but it still really hurts that he would even go so far as to try to. He lied to me one too many times. I just wish that he could've been more honest and made the right choice. In the end all he really did was hurt everyone, and himself, a lot more than he would've if he was just honest.

 

That's what I suggested that he do, because I care for him, but after a day of taking a break he decided that he wanted to be back with me. I tried my best to let him go before I got hurt, and I just wish he could've let go so I didn't have to get my heart broken. I gave him a choice when he said he wanted to stay with me and figure things out while still maintaining a relationship: either stay with me and stay committed to me, or we could mutually part ways and he could take all the time he needed to figure himself out. Unfortunately, he wasn't honest and said that he wanted to stay with me, that he didn't want to let what we had go, and that he'd try to get over his feelings for T. right away. I gave him every opportunity to do the right thing, I tried to let him go before we both got hurt, but he tried to have his cake and eat it, too. I'm already taking the lessons that I've learned from this to heart. He was my first boyfriend, so it's hard to get over him, but now I know what I want in a relationship, what love feels like, and what I need to do to improve myself for the next relationship I find myself in.