- talking about the kids being sick, how about just work on taking care of the kids, leave the discussion of them being sick for another time or let her start that discussion while you remain brief about it. - as for the half day school pick up, leave a note, write it on a calendar, - her paying car insurance, is the car insured under her name? Let her take care of it and if it's under your name, why? Her car, her insurance, one less thing for you to take care of for her.
You are too available, you help too much I'm sure and it's just something she takes for granted. Get a life, go to the gym, go out with buddies, seriously it's not that hard, enjoy your life instead of wasting it following someone who is currently in a fog and doesn't want you in their life - their loss, not yours, that's how you have to look at it and really you need to start enjoying your life.
