White Bird, I don't post here a lot because I always feel like I have nothing to offer. After 51 hours, I'm still pre-solo, so don't feel bad. But I did want to just say a couple of things regarding your situation. If there's one thing I'm an "expert" at, it's training gone bad!!!
First, you're still way too early in the process to even consider the possibility that maybe flying isn't for you. And until an instructor sits you down to have a heart-to-heart to tell you maybe you should take up another hobby, don't ever let them make you feel like it's not meant to be! You know how you feel up there.
I spent 28 hours with an instructor who was all over the controls, without telling me what I was doing wrong. Hell, he wouldn't even admit that he was on the controls, even though I often felt like I was fighting him! A good instructor will let you make mistakes, short of endangering your lives, of course. Beware of the ones who want to talk all the time, who want to demonstrate constantly.
Don't feel like you owe your current CFI anything. Hurt feelings have no business in learning to fly. If your CFI isn't working for you, he isn't working. Try another. I've been through several different CFIs, and in retrospect, I'm sorry I didn't interview them beforehand. Ask your CFI why he/she became a CFI, and what it means to them to teach, and it might tell you a lot! Despite the stereotypes, one of the best CFIs I had was actually a "time-builder." She was working toward an airline job, but she was committed to teaching in the meantime. One of the worst CFIs I had was a career CFI, who seemed far more interested in flying the plane himself than in teaching. When I expressed my frustration to him, he told me, among other obnoxious things, that if I quit it would be no big deal, because someone else would quickly fill my time slot. He had no accountability, no reason to make sure his students succeeded.
I could go on forever about what to beware of, but for now I'll leave you with one final thought based on what I experienced. I feel now like some CFIs were just testing me all along, almost like they wanted to challenge me by being jerks, to see if I had PIC skills in my blood. So if something a CFI says or does doesn't feel right, speak up and say so! If you feel like your CFI is not letting you do what you need to do, tell him or her. They'll respect your for it in the end, I think. Too often we students think we're at the mercy of our teachers, that we know nothing, when maybe in reality we could be teaching our teachers how to better teach.