Ugh. I'm inactive as well and it's hard enough trying to get myself (and hubby) to even step foot into a church building, let alone, sit for an hour in RS or Priesthood. I would just say to take your time and don't put so much pressure onto yourself that you get anxiety. I see no reason why you can't attend RS and just listen to the lessons without having to socialise with everyone. The times that I had attended church, I was never one to sit and just chit chat with the ladies. It's not a sin to keep to yourself in RS.