I just need advice on my life in general? I keep thinking about suicide?

Hey guys :) Sorry about the long read, I know how annoying they are...

So first, I'd like to say that I'm 14, about to go into high school. I have a boyfriend, and he's so sweet. My problem with him is that he's really...I don't know how to describe it..."mushy" I guess, might be a good description. Not physically, but emotionally. A couple of days ago, he sent me this text asking how much I loved him. We do say "I love you", but it's just something to say, you know? We haven't even kissed yet, and we've been together since January. I told him I felt like we were going a bit fast, and he said he understood, but I felt like I hurt his feelings a little bit. Also, he's a bit protective--another guy patted me on the head and he got "all pissy". Don't tell me to break up with him, by the way.

That brings me to Kaleb. He sits next to me in one of my classes, which my boyfriend is also in. He's the one that patted me on the head. He's really friendly and funny, but he's got a ton of problems. For one thing, he does drugs, pot, to be specific. He's really close to getting expelled because he brought a bong to school and he cusses constantly. And a couple months ago, his best friend killed herself. I didn't know her. I really like him (not romantically, just as a friend, he has a girlfriend). I don't think he really has a lot of friends.

That brings me to Aaron. He flirts with a ton of girls and I've known him since I was like 3. I liked him for a long time last year, and I think I might still like him a little bit. I was at a party today (mostly adults) and we went to explore the house we were in. We went around by ourselves. He grabbed my hand and he pulled me into another room. He also gets really close to me a lot. Nothing has ever happened, though. I'm pretty sure he knows I have a boyfriend.

Finally, the situation at home. My dad is the one that worries me the most. He talks to himself a lot. I do that too, but he does it in public with other people are around. He and my mom hit the rocks a couple years ago, and he even moved out of the house. While that was going on, I was on Google on my dad's computer, and it popped up that my dad had searched "how to save a marriage from an affair". I can't imagine my mom ever cheating, so I think it's possible that my dad cheated on her. I think they're having trouble again, because they won't sleep in the same room anymore. My dad keeps taking out his anger on me, not physically, but he'll yell at me when I've done practically nothing wrong. I also have to take almost complete care of my twin 5-year-old brothers. I'm like the only one who disciplines them or even deals with them. I usually cry at least twice a week, and my grades are dropping. I'm in the advanced learning program.

I only have three things left in my life now that I honestly enjoy: my friends/boyfriend, my mom (most of the time), and horseback riding (I have a horse, and he's my saving grace. I love him so much.). I've thought a lot about suicide, not as something I'd ever honestly do, but I just think about it a lot. I've written in my diary the note I would leave if I ever committed suicide.

Thank you so much for your advice, it helps a lot, no matter what you write, whether it's a joke that makes me laugh or some serious advice :) Again, so sorry about the long read.