Get a HaB sling as they're better for your back.

Get your DH to do some housework.

I keep DS on my hip as I vacuum, he sits in his chair watching me as I wash up, he will do a bit of alone play a day but not much, DH has to amuse him while I cook dinner and that's often taking him to see me!

I use the pushchair for his sleeps 2-3 times a week so he gets used to sleeping without me. It took forever for DS to be OK going into his own bed, I used to feed him to sleep then put him in the crib, then remove my arm over about 5 minutes, leaving him with his bedtime bunny and something smelling of me. He only now goes to sleep in his bed when he wakes up, but I still feed him to sleep and have to sing and pat him to sleep. Small steps are the way to go, if he plays alone for a minute without crying build it up to 2 minutes over a couple of days, before you know it you can have a shower without having to sing "never smile at a crocodile" (I'm still waiting for that day LOL).

HTH!