Question

Hello,
My 10 year old son has relational problems, and has no friends, despite having many opportunities for friends. We've hosted and attended many play dates over the years. Steadily, it has come to be that now none of the kids will come over anymore, and we no longer get invited to their homes for play dates. We homeschool, and do several activities outside of play dates, so he socializes this way, but poorly.
Maybe the other moms don't like me, and I'm the problem, but I think not, because they befriend me often with texts, emails and get-to-gathers when it's not with kids.
Is there anything I can do to help my son with friends? Or should I just leave it alone?
Thanks!