Pelafina, I'm sorry you are having problems with your DP. My first response is he really needs to get a grip and support you, but I know that is not constructive or helpful!
My partner has gone on and off supporting me, but not because he found it disgusting, but because he could see the toll it was taking on me and he wanted things to be easier (and me to be in a better mood) but we have talked about it and he has realised that in order to make things easier he just needs to support me more. Only last night when DD (8mo) woke up unexpectedly in the night he said "thank god for bfing, we don't have to get up and make bottles of formula).
As for when we stop, well that is another bone of contention. DH is not entirely convinced about extended bfing, but we are just seeing how it goes.
Having a baby takes it toll of your relationship anyway so it's not unusual for things to be difficult. Do you express? Do you think DP might feel better if he gave a couple of bottles of EBM to your son, feel a bit more involved.
As for feeding in public, have you been out on your own, or with other mothers and fed in public. If you can build your own confidence up in bfing and really believe that you are entitled to feed DS and feed him where you want.
Have you thought about seeing a relate counsellor to address the affect having a baby has had on your relationship? he needs to too you as a mother as well as his partner. It's difficult for men as they don't have things like mnet or support from their friends in the same way that we do, so they don't know what is normal and what isn't.
I hope you can talk sense into him. Stop bfing when you feel you are ready. I don't know about you but I sometimes feel guilty over the bfing as I am not giving DH a choice in the matter, but the way I see it that is my perogative for carrying DD for 9months and giving birth to her!