How to Stay Motivated Through Injury?

I've been battling with rotator cuff tendinitis on my left shoulder for a few months and was forced to take all my pressing motions out of my routine. A few weeks ago I developed knee pain in my left knee (plica and possibly some hamstring tenderness) and it is starting to develop in my right knee.

I've decided to take a week off of all lower body (knee bending) lifts in hopes of ridding myself of knee pain.

I was wondering how everyone else deals with their injuries?: What do you do to stay motivated? Do you continue lifting around the injury as much as possible? Take time off from lifting completely? Ice and NSAID your way through the pain?