Break the habit now! I understand that you just want her to feel better, but at this age they get so attached to anything involved with sleeping and drinking (eatting too, but drinking is usually worse). I know how you feel, though- in December my husband took my daughter to visit his parents and I couldn't go. She was a lot clingier when she got back, but I got her right back on her regular routine and she got over it. I wouldn't give her a bottle, either, just hold her (if she has a binky, go with that) and tell her she's too big to eat at night. I mean, really, I applaud you for breastfeeding so long, but some of the other baby habits probably need to go! A 20 month old shouldn't really have a bottle at all. And if she is using the sucking to go to sleep you're just delaying the inevitable of her having to relearn to go to sleep on her own- in fact, if she needs to feed to go to sleep at night that may be part of the problem. So throw in lots of extra snuggles during the day, be prepared for a few sleepless nights, and be patient! And I don't dig the cry it out thing, either. There are other ways! I never did cry it out or "sleep training" (that said, under certain circumstances there were times she cried in bed), and my daughter has fallen asleep on her own in her own bed since she was 10 months old.