To be fair, Elena told Bill she was going to the drugstore for a pacifier and didn't come back until morning. I'm sure he was frantic with worry and probably called Linda to help him find Elena more so than to help him deal with the kids.
Bill reluctantly took a job in a private law firm because Elena really wanted them to buy a single-family home. Law firms are brutal for associates even now, and it was probably worse in the 80s. I'm sure he had to work upwards of 60 hours a week to make partner. Bill alluded to it on the phone when Elena called him about the water, that he couldn't just leave early. Back then there was no tolerance for men wanting work-life balance and being more hands-on fathers (not that we always have it now, but we've made progress).
While I sympathize with Elena - raising four children so close in age must be hell - she couldn't have a husband who both brings in a lot of money and does his fair share at home. She was the one who pressured him to take the law firm job, so she had to deal with the consequences of that choice.
She went to her doctor to get an IUD, which is how she found out she was pregnant with Izzy, so she did try to get birth control, just not in time. And when she told her mother about the pregnancy and that she had choices, her mother laid a guilt trip on her that women of means aren't supposed to get abortions. Yes, it was still Elena's choice, but I can see how that kind of guilt trip messed with her head when she was already overwhelmed and hormonal.