Giving blowjobs...?

So my boyfriend and I have been together for a couple months now and we've been extremely happy and would do just about anything for him. Except he keeps asking for a blowjob and I just can't wrap my mind about why I don't want to. There is no part of me that even remotely wants to have his dick in my mouth at all. I'm a virgin, he knew that when we got together and it's not like I'm adverse to sex. I give him handjobs all the time and I'm totally down to have sex, I just can't wrap my mind around giving him head. My boyfriends understanding but I know he wants one badly.  I don't know why exactly I don't want, I just don't want to. Has anyone else experienced this and if so what did you do?