OP: Asacol HD tablets are now available as a generic in the U.S.: mesalamine 800 mg from Zydus Pharmaceuticals. Your doctor and insurer should have known this, and it should be substantially cheaper for you.
https://www.drugs.com/availability/generic-asacol-hd.html
Mesalamine has been a lifesaver for me. I've had pan-UC (throughout the entire large intestine) for 20 years, through 2 kids, and am otherwise quite healthy and live a completely normal life. Thanks to maintenance doses of mesalamine, I've had only a few relapses in two decades, and they've been awful, but there is good medication available. Not everyone is this lucky, but some are, and you may well be in that group, especially since your case doesn't involve the whole colon.
You didn't do anything to cause this. Pls try to get over that quickly so you can move on to disease management and taking care of yourself and your family. It's not easy at first, and is MUCH harder for you because you have a newborn and toddler, but you will get through, and this won't define you or your family.