Re asking how you are etc it must be hard for you. Maybe the best way to deal with a lack of these "normal parts of a relationship" is to not expect them, then you cant be disappointed when they don't come. I am speaking from experience.
If you want to try and mend this I suggest you tell her that you feel that she is angry/upset/hurt and that you are happy to listen if and when she is ready to talk. In the meantime tell her that you are happy to continue to do 1 day a week childcare if she wants you to, when you are better.
However I also think you need to be very careful and be very clear for yourself what your red line is in terms of what you will "tolerate" in order to maintain contact. Please take care of yourself. 
A better word than 'apologise'?
