Welcome to the forums! And welcome back to FitDay!
Are you drinking enough water throughout the day? Maybe a different macro combo would help with the hunger?
Injuries suck but there are exercises you can do while avoiding irritating your knee. I was on crutches for 2&1/2 months this summer and going crazy worrying about gaining weight and losing muscle.
I modified as many workouts as I could and worked up to one leg recumbent biking, elliptical, squats and even blading on one skate using my crutches for support. There are also many upper body and core exercises that can be done without putting any pressure on your knee.
Check out the motivational thread in the Women's Forum, great way to be accountable without being overwhelmed. It's a great group with the support that can help keep you on track!
"Just Do It"