Before exh & I seperated (amicably) we were friends with a couple. Ex more him, me more her.
Since the split he offered me a job & I work part time for him - i never see him in the course of work.
But I do see him socially now & then. The weird thing is he never speaks to me & doesn't make eye contact with me. I thought I was just paranoid but ex asked if everything was alright because he noticed boss blanking me yesterday. I was sat right next to ex & asked boss a question - he answered to ex 

Is he just really uncomfortable with ex & I being friends? Or just doesn't like me??? What's going on, its unnerving me!