Arthritis, anyone?

I need a pep talk!! I love the water, though never a competitive swimmer, I do OK (on my one and only visit to the Chicago masters club, the coach gave me a few pointers on my freestyle and backstroke - but said I look good basically). Now, I'm turning into an ever-expanding mid-40's jello mold - - - and want/need to get back into the pool. But, joy of joys, Mother Nature has blessed me with a new companion - osteoarthritis. Is anyone out there dealing with this? Do you push through aches and pains? Do you find that the pain diminishes as you work out - - or over time, as you increase the number of workouts you do each week? How's your energy level, in the pool and out? I have really hit the slump of slumps, and could use some pointers/prodding/inspiration. And a good joke wouldn't hurt!