overreacting?

So, remember my "friend" who was supposed to watch LD while I gave birth but backed out as soon as the contractions started becoming regular? I haven't heard from her since she backed out. She hasn't shown up for the kids gymnastics class either. I'm okay with all this. It was a rotten thing to do. Well today, i got an email from her, she has said before she doesn't use email because it's too impersonal. Anyway, she gave me some names for post partem doulas and asked if the baby was here etc etc. I didn't reply. I really have no interest in continuing the friendship although somehow i'd like the kids to be able to play. We are both into nature and took them on a lot of nature outings which i don't like to do alone for safety's sake and don't know anyone else that's into it although i plan to remedy this right away in the spring by joining the environmental program for kids.

I am the type of person who forgives easily (i do have the 3 strikes rule though...violate my trust 3 times, you're out) and would easily have done so if she had just said something along the lines of "i'm sorry" or "i was wrong to do that" or any good excuse. Am i overreacting here? I figured since she hadn't called to see how things were we had the same feeling. I mean last time i talked to her, i was about to head to the hospital and she was doing nothing and didn't offer to meet me there or anything. We haven't talked since. What do i say to her?