We all go through seasons where we feel that spark sputter a little bit. Quitting lessons for a long period of time is taking a big risk that you might lose ground. You might consider decreasing the frequency of lessons (ie once per month or twice per month) or maybe taking a summer session off to see how you do. In my early studies, I got messed up if I took even a week off. Now, I can take short periods off and still plug along but my problem solving is much slower when I'm on my own. It is reaffirming to spend some time in self discovery though. However, if I have goals and deadlines, I'm in the studio every week that I can be for the support and preparation.
I agree with many of the others that adding some fresh repertoire might help. Bach is wonderful but he is intense! You could take a slower pace with the Bach and explore some pieces that are easier and that you would find fun.
I disagree with the advice to go find a different teacher. If you have a good rapport with your teacher, talk to him/her about how you feel. I'm sure s/he has encountered this phase in student development before and can help you navigate through it. The suggestion to join an ensemble, orchestra or find someone to play duets with are great ideas. Maybe even attend some master classes, if you have access to them, to hear what other teachers have to say. Getting different perspectives are refreshing but I wouldn't suggest that you abandon the teacher you've been working with just because you feel stagnant.
Hang in there! This too, shall pass! Just keep playing!
So much music, so little time.