Hi J.,
Just to back up a bit, why are you weaning your daughter? If it's because she's a year and you SHOULD wean then, consider waiting a while. Your sweet baby will be weaned before she goes to college, I promise!
If not, weaning is a process, sometimes easy (you're busy), and sometimes hard (she's sick and wants to comfort). Forward and backward sounds like a typical weaning pattern to me, so don't beat yourself up. If she nurses while she's sick, no worries. When she's better, try again.
Be sure that you're giving her lots of emotional encouragement and cuddling--sometimes when our children are weaning we avoid a lot of contact so they don't get ideas, if you know what I mean. My children both love this mole I have on my arm, and during the weaning time I'd make time to snuggle them and they'd rub my mole. If you have some similar comforting aspect (they play with your hair, they rub your tummy, you hold their feet, etc), try to continue with that. It may help a lot.
As for the bottle/cup thing, I personally think it's great she won't take a bottle. You won't have to wean her from one. Encourage her! If you're worried that she's not getting enough to drink, offer her frozen juice bars, at least while she's sick. Give her soup, etc.
Meanwhile, take care of yourself. Weaning is an emotional time for you, too. Honor the process, and hang in there!
K.