I suggest you get help from your nearest Small Business Development Center, where you can get workshops, classes and individual counseling related to developing a good business plan and figuring out how to either grow the business, or sell it. Further, you're talking about a deep long-term relationship with your brother, and that's a tough issue, too.
It does sound like you need something to change, and that you want that, and your brother doesn't. It's time to talk, get help, and fix things.
Tim Berry is the chairman of Eugene, Ore.-Palo Alto Software, which produces business-planning software. He founded Bplans.com and wrote The Plan-As-You-Go Business Plan, published by Entrepreneur Press. Berry is also a co-founder of HavePresence.com, a leader in a local angel-investment group and a judge of international business-plan competitions.