My BF can only cum from giving oral😭😭

So my boyfriend can only cum when he gives oral... during the first few weeks, I thought I was in haven! He loves giving oral and I love receiving of cos but now it’s annoying me... he goes all out during oral, tongue in both entrances and all and he does it so seriously that it hurts... we have discussed this so many times but he does not know when he does it so he does not understand what the problem is. Now I’m thinking of breaking up with him because I can’t clearly take away what he loves doing for pleasure from him. I don’t know