Of course you are stressed out. You are about to have a life changing situation come that was something that was supposed to happen years from now, you have had the "choice" part of it taken away.
I would stop worrying about all of this. You have this work issue due to going without during your childhood.
I have a friend that I was a nanny for her children for a few years. Now, this woman is a college professor with tenure. Back in the mid 90's she was making mid $30K per year. Almost 20 years ago. Her hubby was making nearly 4 times what she made, that's right, over $100K per year. They did not have a glorious mansion, new cars, none of the private schools, no huge credit card debt, nothing that their income did not cover completely with lots left over.
She had grown up rather poor, she had actually been raised by another family member due to her parents inability to raise her and feed her. This woman could go out every day and spend $100 for groceries if she wanted to and they could afford it.
She hoarded food. They had a walk in pantry and it was always so full that stuff would fall off the shelves if you bumped it slightly. Because she had done without food as a child she had a compulsion to always see food as something that she had to have in abundance. In my mind she had way too much. Even with all these children she had food that never got touched. She had so much in there that was out of date, so much that no one even liked! She had to hoard food because her mind kept telling her she was going to run out.
This seems to me to perhaps have a similar theme to what you are stating in your letter. You have a compulsion to work, to "horde" money, to put yourself at risk of a health issue just because you "have" to earn enough. There is Never enough money.
There are thousands of people out there in the real world who have children and they don't work as many hours as you do, some do have help from a sig. other that perhaps you feel you don't have but when a child is involved that a mom always finds a way.
There are moms out there who have 1 or more kids, is single, and only works one job, and lives very happy. Your body is changing and your are having natural anxiety, top that off with the environmental issues...you have a recipe for one way stressed out L..
Take some time, take a deep breath, take a moment to close your eyes and visualize your child. He/she is snuggled up inside listening to your heartbeat. She/he will love you no matter what. Life has a way of working things out.
Facts are that most normal people have to have both mom and dad working. I do think that choosing a lifestyle that is affordable for your income is worth weighing. Since he is not making enough money, may not even have the education or skills to make more money, and you may have to face facts that he is happy like he is. Not a bad thing, you are the one that seems to be worried about the extra's.
Take a piece of paper and list the things you have that you can afford. Like your home. Is it within your budget, 30% of the whole income should be considered how much to budget for housing. Including utilities and insurance. Can you find less expensive but still adequate housing? We lived in a 1 bedroom apartment for the first year of my daughters life. She slept in her crib in our room.
You have been with this man for over a decade as a friend and over half that as a couple. You know him, you care about him. You both need to sit down and talk but he is not going to automatically have the same issues as you do.
Give him some time to process that a baby is coming. For most men a baby isn't a real thing until they actually hold that baby and look in it's eyes and fall in love with it. They do not play Mommy with their baby dolls as a child, they do not see a baby at the mall and automatically think of how cute and want to go play with it, they are just not wired that way. Women are typically wired to be a nurturer, it's instinct. That is why you are stressing out over this and he is not. He may not even "get" what has you so worried until the baby is several months older and he finds he does not have money to go get diapers. Then he will "get" it and start the process of being a better provider. Give him a chance to grow up, you cannot make him into a dad, he has to go there himself or he won't be the best one he can be.