What should I do about my husband? HELP!?

He seriously has bi-polar issues, One second he's happy, and chatting away with alot of compliments and then he gets very sinister, mean, attacking, arrogant. And I'm like totally confused. Then he's very quite, not talking, ignoring, staying on the computer for hours and hours. We go outside andhe wants to come but then begins the complaining, snide remarks, and aggresive behavior. We have two children together an I am a very loving person. He does not belive in taking medication, he believes in the Divine Power I guess for the cure. His family also has the same mental issues. i dont know what to do, and leaving him is NOT the answer, because we have been together for seven years and i love him. Is their anyway I can cope without getting so tangled with his mental issues, and I also don't get so drained out, or depressed like him?