Is it normal for me to be in love with my best friend?

I've known my best friend since he was in his late teens and I was in my early 20's. We are like brothers, and we're very close with each others families. We've tpped each other's junk, seen each other in the shower. I saw his hard on in a hot tub one time, and twise we had piss races, lol. We even shared a bed at one time (nothing that I know of ever happened). I was about this time I started having feeling towards guys. I bought my house a few years ago and he spent almost every weekend coming over. We'd sit in our boxers and watch tv, movies, or listen to music. As time went by he became more conservative and when he'd stay over he would wear PJ pants. He's lived with me twice and the first time was the way things had been. This last time, which he just recenty moved out, things were really great when he moved in last here showing up at 2am one morning and asked to move back in. He said a few times that if I wanna have a threesome with him and a girl both are freinds with. He joked about dicks, he'd make comments like we were a couple. In April I told him that I am bisexual. After I told him he became very quiet, sometimes after he got home from work, and that's also when he started dating a girl out of the blue. Also after I told him he'd come out to the living room in his towel and usually have his crotch in my face or walk in from of me half naked and and go back in his room through the kitchen. We've gotten in some fights and the last one he started I asked him if he wanted me to do something to him and if that's what is problem is. He stopped texting, as the fights were through the text. About two weeks ago I went to pick him up one morning and let me in with his shorts undone and his buldge through his boxers was hanging out and he wass walking around his place like that for awhile before we left. I've been wondering if he's curious since he's been acting like this since April and he's gotten weirder in the past 2 or 3 months. When he was moving out he said he doen't want a hug and make it mushy. When he was packing I asked if he wanted to talk but he said not right now (which he still won't tell me whats wrong) When I dropped him off at his new place and I went to leave he wouldn't look at me and when he did he had tears in his eyes. Since that morning I wanted to ask him if he wants to mess around. He has hardly text me, for about 2 weeks now, and just keeps telling me he doesn't want to talk about it yet (I've stopped pushing him too). I really want to ask him if he wants to mess around, but need advice. I don't want our freindship to end. Any suggestions?