I can't say whether you should or shouldn't quit but I can say this... When I was going into my senior year of high school I almost quit. I felt like I had a love-hate relationship with the sport, the gym, and the people in it but I had then felt more hate than love at the time. For me, gymnastics was a sort of "happy" place where the outside world didn't exist for a couple hours out of my day. Of course things weren't always happy but it just gave me something other than life to focus on. About 2 months before season was supposed to start, my coach made a wonderful suggestion-- one of his former gymnasts had gotten a job coaching the high school team and he suggested that I along with a few other girls join the hs team. At first I wasn't so sure, but I came to love it. Honestly if I wasn't a Senior, I would have done it again. When it came to college, I made a little deal with myself-- if the school I chose had gymnastics, I would go out for the team, but I wasn't going to go to a school JUST for gymnastics. I could have been on a D3 team but ended up choosing a school which didn't have any gymnastics at it. But I did end up getting a job coaching at the local club in town which eventually lead me to getting a job as an assistant high school coach at a school nearby. I LOVE my job, but there are definitely plenty of days where I think I really miss being the gymnast. At least for me, I don't think I will EVER give up gymnastics completely... I will always find a way to be involved... and that is what I would suggest to you also... There will probably always be a part of you that loves gymnastics and if that's true you will feel the need to continue it in some way. If you don't continue as a gymnast you could always try coaching OR you could try diving. I did diving for a year and while it wasn't for me, I know several gymnasts who are still using their gymnastics for diving. It is fairly easy for gymnasts to pick up and if you are good enough you could get a scholarship. Just a thought.
Hope this makes your decision slightly easier! And good luck in whatever you choose to do!