He doesn't have to be brilliant, outgoing or wise. Nor does he have to graduate two years earlier just to prove that homeschooling is better than highschool. Know that if your child is behind at school it doesn't mean either your or him are a failure. Nor does it necessarily mean homeschooling is bad for your child.
Children learn at different speeds and there's tons of kids in school who fall behind too.
Grades are not everything. Accept that your child may not be as popular as you want. If your child is lonely, then look for ways to help her make friends, but if your child is content being on her own, then accept that. Being popular is not the same as having social skills. As a homeschooling parent you may find yourself being pestered about whether or not your children have social skills.