ENigma, only you can do what's right for you guys.
There are a couple of options if you decide to take her Tuesday.
Drop her off and go and sit in the car for a short time (10mins or so - or until you can't bear it) then creep back inside and see if you can see through the door/window to see if she's OK. Don't let her see you though, cos if she is settled, you don't want to disrupt her again. If she's still unsettled either repeat the process or take her home.
I remeber when I was learning to walk in high heels and some one told me 'pretend you're confident, and no-one will know the difference". This is similar. Children can pick up on your stress. I don't mean be blase about it, but be cheerful and upbeat. Tell her all the wonderful things she's going to do today. Most improtantly kiss her and tell her you will come back for her shortly.
Tell her that every day you drop her off and soon she will trust you to do as you say.
It isn't selfish the way you are feeling. I truly wish I had had that choice. Children definiatley don't need daycare but if the opportunity is available there are certainly many many benefits for the child too.
Good luck with whatever you decide.