The times I've had to take a break from training were always hard, even depressing. Just remember two magic words, lad, that should make you feel a lot better....
MUSCLE MEMORY!!!
Everything's still in the bank. Especially when you've done something as long as you have, it's all there. The techniques are part of your central nervous system, by this point! So all that you need is the will.
And so far as that goes, the trick is, don't try to do it all at one time. Each training session, go for just a little more than you did before. Just a little more! The trick is to set up your training so you don't do so much more on one day than the day before that you have this awful prospect of having to do at least that much, and maybe a lot more, again today. I remember that no matter what I was doing—weights, intervals or whatever—a really big training session, way out of line with what I'd been doing previously, came with a hefty price tag: the sense that I had to keep working at that same level from this point on. And I couldn't do it! So overperforming isn't good for morale, either, which is just as important as anything else at this stage.
That's why it'll probably be better to just add a little bit each time you work out,till eventually you're ahead of where you were when you stopped. It's just too hard to have to face these massive increases in performance each workout....