Only about 4% of the U.S. population has AB blood type, and there aren't other blood types that are compatible, so that explains why you're having difficulty finding a match.
Are you signed up to be a blood donor and marrow donor? Your blood type is still an issue with these forms of donation in terms of matching, but at least you can expand the possibilities for donating to someone in need. They are also forms of donation with significantly lower levels of complication compared to liver donation.