evolvingjp-I just wanted to say that it's great that you are there for your partner because I know how tough it can be dating an ACOA (I'm a nightmare!lol).
I think Givelove's idea is a very good one and also you could try reading Loving an Adult Child of an Alcocholic by Douglas and Deborah Bey.
I can't speak for your partner, but when I push my boyfriend away it isn't anything to do with him, really, it's because I learned early on that trusting someone led to pain and rejection. It was very difficult for him, but I think he realises now that it doesn't mean I don't love him.
I wish I had some magic words that could make it ok for you and your partner, but unfortunately it takes time and lots of love and patience. But it CAN be done, there are lots of people on here that are proof that ACOA's can have long, happy, healthy relationships!
Lots of luck to you both x