99% solo here, too. Same reasons as most, just never seem to find people who like to do it, and also have the same schedule. Some, just aren't safe to hunt with... leaning a loaded rifle with the safety off against the side of a polyester blind... bonking you in the face with a rifle barrel as they swing on running game... you know.
I've had some great hunts with friends, but moved to a different part of the state a number of years back and just haven't made connections with like-minded people, yet.