Same thing happened to me last year, I just lost all motivation. I ended up stacking on 30kg and getting weak as fuck.
I used to use my anger to push me in the gym, and I was just too fat and lethargic to care.
I saw a picture of myself at my sisters wedding, and was disgusted at myself. Couple that with a few other bullshit dramas, and I got real mad. Now I'm destrominating the gym and losing the weight I gained.
Anyway, the point is, you need to find something to use as intrinsic motivation to light a fire under your ass