oh sweetie

. hugs to you (((((krazibean)))).
i'm a bit practical, so forgive me for launching into the practical stuff first. re: the money. i think it would be a good idea to drop off the check for $200 immediately. this is how much you know you owe her, and it would be good idea for you to stick to your word.
secondly - is there any way of verifying how much you actually do owe her? have you kept notes/receipts of the times you did/did not pay her? i think it is essential that you figure out whether you really do owe her the money she claims you do. sometimes Ts make mistakes, but sometimes we do as well. if you do owe her the money she claims you do, i think it's very important that you pay her back. also, it's essential that she asked for it - this is her job, her livelihood. it's not about her caring for you or not, but she needs to pay her bills just like everyone else does. she has probably been kind to you whilst you continued to be her client, and let you keep an account, but a lot of clients when they say they want a 'break' do not ever return from that break, so Ts need to chase them up for monies owed before they lose touch with them altogether.
if you are certain that you do not owe her the amount she claims you do, i think you need to give her a call, or email if that's easier to sort it out. maybe she has made a typo, maybe she has added up someone else's account, whatever. but it is important that you pay her.
as for whether to return: i can understand why this would feel like such a rip in the therapeutic relationship

. with my old T, i often felt locked in power struggles with him too - but if i called him on it, he was receptive to that and would become a lot more supportive instead of confrontational. if your T is taking everything like a personal attack, then it may be the case that you have outgrown what she is able to offer you.
i took a few breaks from my T, but i always discussed it with him in-session first. i found it useful just so that we could be clear that i really did intend to return (instead of taking a 'break' as meaning 'i'm not coming back'). i think the first time i took a break, my T really was surprised that i returned (clients must terminate that way often, huh?). but eventually he got used to it

.
my suggestion would be this:
1) clear up the issue of what you owe her. firstly, figure out exactly what you do owe her and talk to her about it if you think there is a discrepancy. second - once you've both agreed to the sum, pay it all off immediately (if you can) or arrange a plan with her so that she knows it will be paid back in time. i think it would be too hard to find an emotional connection and safety when there are practical matters like this to be addressed.
2) when you have paid off the debt, or at least embarked on paying it off, send her an email addressing your concerns about where therapy is going/where the relationship stands. express to her your concern about how you feel like you are in a power struggle at times, and also that you feel she isn't receptive when you bring these issues up. see how she responds, and go with your instinct from there. if you decide to continue therapy, then great

. if you decide that maybe your time has come to move on to someone else, then maybe you could go in for a termination session, to sum up/celebrate achievements/leave on a good footing. it will always help should you want to get in touch with her down the track.
eta: i'm sorry - i just read over my post. i sound strict and overly hung up about the money issue. i don't mean to be that way

. i'm sorry if i hurt you at all - i'm really just trying to help, in my own bumbling way.