blowjobs

I've made the personal decision to not give my boyfriend blowjobs. I don't see it as "intimate" I honestly find it kind of disgusting and I'm just not comfortable doing it. I've talked to my boyfriend plenty of times about it but he still always pushes me into doing it. he guilt trips me into doing it by saying that he does all this stuff for me but I don't do anything in return and I understand that but it's still a personal decision that I've made. how do I get him to back off or convince him that it's not a big deal?