Ok... So I have no leg to stand on with this. I am gay, currently row varsity for a top school in Canada, and am baisically at the same point you are as far as being out minus the boyfriend

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My advice, however, would be that it doesn't get any easier to come out if you wait and get to know the guys. Further, no amount of success or accomplishment once you get to college will change this.
Here is a little personal anecdote to help illuminate my point.
There was a guy who rowed for our crew for a couple years who everyone assumed was gay. Baisically he was a bit shwishy and effeminate and generally got a repuatation for not pushing himself very hard, which people associated with being feminine and weak; essentially gay. At the outset it was good for me because it deflected any potential attention off of myself (not that I drew much). At the same time, however, watching the way that the other guys reacted to him was tough. As far as I know, no one ever said or did anything to him, but there were certainly comments. Guys would say that he was just there to watch other guys in skin-tight spandex and often when he went to shower one or two guys would think it was funny to run out and cover themselves as he walked in. The fact that he wasn't really all that good certainly didn't help anything.
Where I should have been the guy to step in and stick up for this kid, I just ignored it and, at the time, felt relieved that it wasn't me. The whole situation was shit. Looking back, I deeply regret not standing up for the kid, but at the time I was still in the JV boat and really didn't want to draw attention to myself, especially when it was the senior varsity guys who were the ringleaders in most of the stuff. Anyway, the guy left at the beginning of the same year I made the varsity boat and that was sort of the end of it. What I failed to realize was that if I had stood up for him from the beginning it would have made both our lives easier. His because maybe people would have cut all the comments and the shit and included him a bit more (let's just say when we were heading downtown or partying after competitions he wasn't the first invite), and mine beacuese I wouldn't be in the position that I am now. i.e. I am the lightweight captain, row in the heavy 8+ and essentially have built everyones expectations of who I am up so much that there will be fall-out when I come out. Baisically the crew is a lot of fun, and some of the stuff that we have done together seemed fairly innocuous as long as everyone participating was straight, but throw in that someone was gay and people willl freak.
Anyway, over the course of my time on the team, I have made a few really close frinds who I am out to, but most of the team doesn't know. For the past 3 years I have felt that I had to punch above my weight (wihtout getting into a lot of details I am small for a rower) and prove that I am on the team because I am driven to compete, driven to excell and driven to win. I felt that if I did this long enough and well enough I would be in a position where it would be easy to come out without anyone hassling me or questioning my motivation for being on the team. Hell, if they did I could ask them how it felt to be slower than a fag. I thought that all I needed was for people to respect me as a rower first and then life would be easy. Turns out this is wrong for a couple of reasons. Number one, people don't want to be respected by something they do, they want to be respected as a person. Hiding who you are, essentially lying to yourself and others is not a good way to make people respect you as a person. Two, the guys who you wanted the simple one-dimensional respect from end up becoming a big part of your social setting. Essentially they're your friends. So what's happened is that you have wound up going through the trouble and effort of building these relationships with your team-mates, who you often can't help but like, and in essence raised the stakes of actually coming out to them in that if they react badly it's only going to hurt that much more.
The reality is that you're in a shit situation. There is no easy time to come out and either way it's going to be tough. Knowing what I know now, I think I might have been better off coming out when I first hit college. At the very least it would have saved me from being implicitly involved in some stuff that I am not too proud of. I would also say that staying closeted, as I am sure you know, is not to fullfilling of an option, and you don't feel any better about yourself as time goes on.