Originally Posted by
Spectral
It's pretty hard man, I've experienced that. I think the best thing to do, if possible, is to have some workout partner or someone you can at least talk to workouts about. It's a lot easier to get motivated when you're going to have someone that gives a crap about what you've done, at least for me.
The other thing might be to start your cardio with zone training. You'll go slow, but there's an actual reason for it, so you don't have to feel bad. You'll build up nicely that way too.
The weights... meh, coming back is hard. I just started lifting again for the first time in awhile the other day and was struck by how weak I was. When you just suck it up and do it, your muscles will feel good though.