Hey Twin Sis - sorry to hear you are having such a hard time with the sleeping stuff. Can you get your hands on the No Crying Comforted Sleep Solution book? She has a program designed towards very gradually weaning your baby into sleeping on their own, which might be worth a try.

We reached desperation point some months ago and in the end *nothing* was working and we ended up in a residential mothercraft clinic to get it sorted. Which worked a treat but isn't for everyone...just wanted to mention it as you might like to consider it if all else fails!