I too suffered an ac separation @ 7 years ago. I had to cut off my shirt because I could not lift my arm above my head, could not brush my hair or teeth, etc etc. I listened to my ortho (something that is very hard to do sometimes) and I used a sling and rested it for much longer than I thought I was capable of doing.

I never needed surgery. Through consistent physical therapy, I ended up being as strong as ever. I do have a noticeable bump atop of that shoulder (or is that a chip on my shoulder?) and still experience pain time to time when lifting my arm over my head. But two out of three doctors told me surgery was necessary and I decided to go with the "conservative" approach and boy am I glad. Beware of all of those doctors who immediately want to cut you open. Make sure that they don't need the practice.

Rest up and Good luck.