good luck tomorrow. and try to relax.
what i did on the day of milu's spay surgery was doing things to keep my mind off of it. i went shopping and did other things to keep myself from worrying about her the whole time she was at the vet.
i also waited till the last minute to take milu in to the vet, because i didn't want her to be away from me for so long.
i took her for a little walk outside the vet's office before leaving. i also brought her bed, her blanket, and her piglet for her so she can have it with her there the whole day. (you can try to sleep with her balnket the night before so it smells like you so abby can smell you and not feel lonely when she wakes up from the surgery.)
good luck to abby and mommy tomorrow!