Wow! I could have written your post right down to the elmo sheets when my DD was that age! Hahaha.

You definitely haven't made a rod for your own back, don't let anyone tell you that! You have given your DD one of the best presents you could and she will be better off for it!

We did exactly what Kitt3n suggested, squeezed her single bed in next to ours beside the wall. She loves it, and it wasn't a struggle at all. She is still happily there a year and half later and when she is ready she will move into her own room. Because hers is a toddler bed, there is a bit of a drop down to her bed, so i propped it up on some books so there is less of a drop (she likes to sleep with her head right next to mine), but i left it a little so it is obvious which is her space and which is ours.

I recommend keeping your DH's bed set up though for when you need some time alone together, nothing worse than to look up and find a little someone watching you