Have you tried walking? Doesn't really require a routine, you can check out the scenery and go at whatever pace suits you, energetically or moseying along. I have significant physical limitations and this is the only thing I can stick with (and I no longer own a car, so walking is built in to my current lifestyle).

Only do as much as you feel good doing. Most people when they start out do too much or expect exercise to give a bad feeling, I know I did 2 years ago. Hell, I was even famous for hating exercise in a show called Nerds FC. But recently I have started running reallly really long distances at an "easy" pace, and it is the most enjoyable, meaningless thing to do! When you enjoy it, you won't need a "routine", you will just let yourself indulge.