Hey OP, I'm not part of the LGBT community but I grew up in a very conservative, religious household. I'm an atheist and that caused a lot of tension in my home life, I was yelled at, grounded, beaten occasionally, forced to go to church, and made to listen to sermons about how terrible atheists are and how I'm going to hell. I had, what felt like it at the time, a serious relationship that ended poorly and it ruined me for years. I didn't date again until I was 20 out of fear of being hurt again. I was depressed, having panic attacks regularly and suicidal at times. My parents didn't believe mental health was real and refused to get me the help I needed. All of that wasn't to diminish what you're going through or out-shitty-childhood you. I wanted to show that I relate to you on a similar level.

I just want to let you know that it can get better if you allow it to. While I had a lot going on, I made it harder on myself than it needed to be. I've come to realize that I could have been happier if I had not let that relationship drag me down so much. If I had accepted that my parents were intolerant of my beliefs and that talking to them about these things was unproductive and only made things worse. If I chose to confide in my friends about my depression and suicidal thoughts instead of talking to people who didn't even believe depression was real.

Your parents strike me as the types that are "fine with the gays as long as it's not one of my kids". It may not be the best idea to come out to them right now, you could be putting yourself at risk. Of course I don't know you or them and that could be entirely wrong, but you feel the need to protect your siblings from them so something tells me that it would serve you well to protect yourself from them too. At 14, you may not know what you want to do after school, and that's fine. You have plenty of time to work something out. But I would encourage you to find a way to independence as soon as possible. Be it going to a college out of state, taking an apprenticeship in the trades, or finding a job that pays well enough for you to get an apartment with/without some friends. Being out of your parents place and free to be yourself will help a lot. But you've still got a few years before that time comes.

While you're still there, and this may sound shitty, you might be better off in limiting your contact with your parents as much as you reasonably can. You want something from them that they can't/won't give you and you're doing yourself a disservice by trying to get them to be something they're not. You have a therapist, which is good provided they actually want to help. They can help you heal from the shit your parents are putting you through. And while your friends may not be able to relate to your problems much I think you'd be surprised in the ways they can help. You don't have to experience the same things as somebody else to be empathetic and supportive. Talking to your friends candidly about what's wrong and how you need help could be a game changer for you. Don't push off the support of your peers for fear of being unheard. If they're unwilling to be there for you, they're probably not your friends.

As for your relationship; if it's over then there's not much you can do about it. It hurts, it feels like your world is coming down, and you're unsure if you'll ever feel that way about somebody else. You will. It'll take time, but you will. There's a fine line between mourning the loss of a relationship and ruminating. I hope.you find it sooner than I did at the time. One day you may look back on it and regret how long you let it affect you. You'll see lost opportunities, days wasted feeling terrible, and potentially how little that relationship meant in the grand scheme of things. All of that is easy to say years after the fact and you may just brush it off because right now it feels awful. But don't let that be the only thing you feel. You're young, partners will come and go, and that's going to really suck at times. But you'll find someone eventually, when you're ready to.

I don't know you or your full situation so I could just as easily have missed the mark entirely or made an ass of myself, but I hope my rambling offered some comfort or perspective to you. I hope things get easier for you