I would hazard a guess that the 'guilt' could be more sadness at moving on to the next stage, and you missing being needed. I've recently got DS to put himself to bed (yes it took 2 1/2 years LOL) and while I don't necessarily feel guilty about pushing the issue a little (altho he was actually very ready) it's still kinda sad that he doesn't need me to get to sleep any more. Sometimes I want to lie down with him like old times, but I'm just giving it a bit of time so I don't undo what we've just achieved! hehe. We now have extra cuddles and stories and things before sleeping, so perhaps you could add something new and special to her new bedtime routine to help fill that little void for you both.

*hugs* and well done I agree that you know what sort of cries you need to respond to, don't doubt yourself