I know what you're saying about working out. I tested the water last week with some weight training.
I did a bit of a random workout routine because i wanted to see which movements I was comfortable with, and which ones i wasn't quite ready for.
Shoulder press felt tight to do, but i racked on 15kg per side on bench press and repped them out. I didn't want to push any further. Typically i can do 30kg per side. Arms was fine, did some curling and various tricep extensions. Also did a 30 minute jog and some abs.
So all in all it took me about 5 weeks to get back into the gym properly. I workout regularly and actually it was nice to give my body a rest for a month - i'll be fighting with the new years resolution people in January
As for my chest, it's still excellent. Nice and flat, no scar tissue yet, tiny bit of swelling but hardly worth mentioning.