Congrats! Consider your current circumstances new trail to adapt to. You have certainly learned how to do this by now. Do as many good deeds as possible to ward off being depressed. Get out and strart building your new life ASAP - the sooner you land on your feet, the sooner you will find ways to derive happiness from your new surroundings. Spend a lot of time with friends - share stories of your travels and catch with them on their stuff. Just like the AT, you will be energized by the people around you or energize them (which will make you feel good).
I stayed with my parents for exactly two weeks. We still joke that I called it "living on a submarine." Tons of rules, very little privacy, small living quarters and the little ****zhu dog which I re-named my XO. Although I very much appreciated them opening their home to me, I couldn't wait to get out.
Good luck to you! It may not feel like it, but you have a great opportunity right now to start a phase of your life from scratch...with no obligations and a clear heart that thru-hikers know well.
As for your knees - what did you do on the AT? Pop some advil and keep moving ; )
Happy hiking!
TTF