I am no expert, but i am sure you are a lovely and caring person. From what i have read, (this is the only way i can figure out the type of person you are implying to be) so far you are good enough for anyone, no one is not good enough. Humans think something what they are doing is “stupid” or “bad” which gives us a sense of insecurity. In fact, its all in your head, this sense of you are doing everything wrong is all in your head, no one would think you are not worth him, and i am pretty sure he doesn’t feel the same way either. This is linked to appearance, humans can sometimes believe that their appearance should be spot on, which doesn’t allow them to fully live, such as me. I think everyone is watching me, secretly talking about my attire or body shape, which makes me very insecure. But again its in my head, no body cares what i’m doing, they are probably more worried if they left the stove on, ya know. I know this is irrelevant to what you are saying and asking for, but its all the same. Never think you are a crappy girlfriend, unless your physically hurting him that is., bc i am sure you are a lovely woman, which is why he loves you and stays by your side. Though, if you think you are a “crappy” gf then do something about it, get on your feet, tell him how you feel, be open with him, ask him what he wants, not only will this hopefully help you gain some more confidence in yourself, but it will improve your relationship. I am sorry if this didn’t help, or if i blabbered on too much, just please don’t treat yourself like you’re not worth it, bc girl you are, you are totally worth it!