I bet having a friend is going to make a HUGE difference for him. If he hasn't had BML the correct way, his coat will look bad. BML is great, so long as it's followed as written! My gliders have very lovely, silky coats on it. However, if he hasn't had a lot of attention, and no friend, he's probably overgrooming out of depression and boredom.
Is he neutered? Be careful when you do get him neutered if he isn't already. In fact, I would highly recommend getting a laser neutering. My reason for saying this is that if he has a tendency to overgroom, it's my experience that he may be more prone to self-mutilating. I experienced this with Hercules after his neutering. He had a "normal" surgical neuter. It was a bit of a nightmare, because he pulled all the stitches out over night, and I had to take him back into the vet the very next morning for another surgery.
Anyhow, your vet will most likely want to wait to do a neuter for at least thirty days, which is what my newer vet does. She wants two clean fecals before adding the stress of a neuter to a new glider.