Ok, you're lookin' for some, "experienced advice", rite, Nat?
Well, as old as I am I've got THAT by the tub fulls! So, here it comes. ALL the answers to every question u asked and every worry, wonder, and/or whatever u mentioned above, r NOT going to come from any of us, but FROM U!
The BAD NEWS: U must figure out and resolve all these issues yourself! The GOOD NEWS: You're young and have all the time in the world to do it!
It seems the most vexing of your issues is with this "boy friend". I didn't read where u say you're gay or bi. Have u even accepted THAT yet? If not, that should be your first order of business! If u have already accepted that, then u need to have a discussion with your "boy friend" over drinks some time. He sounds like an accepting, open person. Whether or not he'll want to remain close after the "discussion", well, no one can predict that! But, at least that issue will be handled! And, u can move on to the next one! And, so on and so on. And, before u know it, you'll be an old fart like me. With wonderful memories, few or no regrets, and looking forward to the time u have left, as well as looking back on the life you've enjoyed!
There u have it grasshopper! Hope u took notes and enjoy your road ahead!