Advice needed on oral

So my fiance and I have been together over four years now. We our expecting our first child and I feel terrible that I don't give him oral.....

I haven't in months.... its not that I don't want to, I do, I know it makes him feel good, I can just never pull myself to actually do it.. We have sex all the time, but I am worried if I don't start giving him oral at least more occasionally that he might... look for it elsewhere.

Any tips how to actually, just go for it... (haha)