Bearess: It's awful, but the Catholic Church is very strict about this. Your priest is not hardline - he would be not doing his job if he let you take Communion, as you are in a state of mortal sin.
This was exactly the reason that I had to leave the Catholic Church and was received into the Anglican church. Once you are in a relationship after a divorce in the Catholic church, you are stuck as far as communion is concerned. You just can't participate. Although some priests may 'turn a blind eye' I felt it wasn't fair of me to ask them to do so, and it just felt wrong anyway that I was being 'officially' banned from communion because of my past.
It was very painful to leave the Catholic church and upset my family a great deal - I am xth generation Catholic - I had letters and visits from priests all over the country trying to persuade me to change my mind and seek annulments. But that route can be painful and didn't feel honest either.
I found the Anglican church far more welcoming, forgiving - and of course it's far more progressive on just about every front than the Catholic church.
You do have the option of getting your partner to apply for an annulment of his first marriage - you could speak to your parish priest about that if you felt it was a route you wanted to go down. But it isn't easy (and would require a lot of committment from him).
Good luck, I hope you find a welcoming spiritual home somehow!