It depends. If you can't live without this person, you have to find some way to cope. If giving head is a huge deal to you and there are no options for you to get it elsewhere (like opening up the relationship to some degree), it may be something to break up over. I am extremely orally fixated. I don't feel satisfied if I go a day without my husband's cock in my mouth. If my husband didn't like getting head, he wouldn't be my husband. It just depends on your priorities.