Sounds like you are hanging in there. Glad you are keeping up with your exercise. And even if they are mostly married, they have friends and relations who aren't.
On the fighting over pick up & dropping off, try to turn it from a power struggle of needs to asking her if you could both step back and look it it differently. Then say you are more worried about the impact on S and making the next decade as easy on all three of you for the good of all of you, but esp. S. Then ask her what she thinks would be best. Given some of the things you've said, she may just throw her wants in, but she also may appreciate that you've de-escalated, and also shown her respect by asking her opinion.
On the Prozac: go to a psychiatrist to get it rather than your regular doctor. Anti-depressants are a bit of an art, as different people respond to different ones (& we don't know why). Still, psychiatrists generally are able to make decent hunches about which one will work based on having worked with so many people. The psychiatrist will want to see you in about 3-4 weeks to assess if the drug is working, and may try something else based on the results. It takes about 3 weeks for most to have an impact, and as psychiatrist will be better and weaning you off when it comes time.
Some need a more sedating anti-D because anxiety is an issue. Paxil is often used. If your D is more the lethargic type, than Prozac or Wellbutrin are often used. But it is the combination of symptoms that gives a psychiatrist the hints of which may be right for you.
Hang in there. You're a very strong person going through all you have and taking life head on.
Me: 50 W:43 S6, S3 M: 12 yrs. T: 17 M is bad & Not happy Bomb Mar '14 S 5 Feb '15 D Bomb 13 Apr '15 (but "no hurry") DB Coach May '15 Wants proceed on D Aug '15 Starting 1-on-1 negotiations Sept '15