Re: boobs, beds, and babies
Just another perspective:
I never really used CIO for any of mine. I have had varying degrees of nursers/sleepers. From great to awful, from super needy to very independent...
If I were in your shoes I would start trying to night wean. I'd do that in conjunction with moving LO to a new bed. At 18 mos old, night weaning and independent sleeping isn't beyond her abilities, but she will need your help to adjust to it.
Remember, that there is a difference between leaving your helpless infant child alone to cry for hours, and letting your 18 mo old throw a tantrum b/c they can't have what they want (boobs). Those are two very different things. Letting her pitch her fit while you just calmly hold her and talk to her is not going to make you a bad mom or make her screwed up. It will teach her boundaries and teach her that sometimes she can't have what she wants. (And believe me, I DO understand! My 24 mo old is JUST like this - with everything - crying hysterics anytime anyone says no about anything. It's definitely no fun.)
It's totally your choice to do whatever you are most comfortable with. Letting her continue to sleep with you and continue to night nurse won't hurt her, either. Eventually her sleep habits will get better. You haven't hurt her or done her any disservice by allowing her to nurse to sleep. That makes the most sense for a tired mama! Don't beat yourself up about it.
But if you are ready to change her habits and yours, don't feel bad about that, either. You have to do what works for you, for her, and for your situation.