seriously man, she wants to feel loved. you should take it as a compliment that she wants to blow you so badly. it would only be degrading if she felt degraded. It's what she wants, so how can it be making her any less of a woman? think about it
My suggestion-- make sure first of all that you are clean and fresh smelling down in ManLand. maybe a quick hair trim to avoid the hair stuck between the teeth gig, maybe going as far as a quick shave, tho I advise against this as the stubble when growing back can annoy both parties. Get an electric mustasche trimmer with the length adjustor and set this for the shortest trim possible. This in itself should act as a turn on for both parties, unless I am seriously perved. Finally why not try to instigate a 69- this will get each party satisfied while leaving no fellings of guilt.
If you really don't want your cock sucked and you don't care about her breaking up with you, don't worry about it. But what are you losing, what is she losing, for trying at least. I completely understand why she would leave, or perhaps give blowjobs to other guys... to be denied such a simple part of intimacy with someone you're in a relationship, to be denied the opportunity to get to know that part of her bf's body in another way, I could understand how that would make her feel degraded. It depends on how serious your relationship is, but like others have said, it's about trust, in the least... do you not trust her to make decisions for herself about how she would like to show her feelings for you? If not, forget about it. You shouldn't do anything you don't want to do, but make sure you really don't want to... and are capable of facing the consequences.
She wants to go down on you. It's not like you're making her. She's obviously frustrated that you won't let her. This could cause problems, so I suggest you just go with it. It can't be degrading if she enjoys it.