Has my mom been manipulating me this whole time?

I was about 9 when my parents split i remember my mom coming up the stairs and asking me who i would want to live with if they got divorced... I also remember thinking "i don't know" but I told her that i wanted to live with her. It's been over 4 years now my life has been good my dad just got married and I want to move in with him. My mom is aware of that (i did not tell her) and ever since he got married she's been nicer. I was talking to her about a problem between my step mom and my grandmother i was pretty upset about it and all she said was "Don't let your dad guilt you into things" she has said it before when I wanted to go down to my dads more. I don't like my school have gotten very poor grades since I moved up here and genuinely have been depressed for the most part. She wants me to get a job which I want one too but I believe it's just so she doesn't have to buy anything for me anymore. She groans when I ask for lunch money 20 bucks every 2 weeks my dad pays child support 100+ a week. She thinks and has said he only wants me to move down there so he doesn't have to pay anymore child support when on the other side of things she is the one receiving it. I don't know what to do should I move down there where i am actually happy or should i stay here where it may be more reliable... If i do move down there i fear my mom will stop talking to me altogether.