How do I help my significant other through this problem?

Just to get it out of the way, therapy is NOT an option. So please, do not suggest it. Also, sorry this is so long!

My husband and I have been married for about 1.5 years, and together for 4 years. In that short amount of time, a lot of changes have occurred within our relationship. We are about to have our second child, have moved a couple times, and have seen some extremely rough financial times.

When I had our first son (we weren’t married yet), my husband had to work many hours because we both lost our jobs when I was 3 months pregnant, he was able to find something and I had no luck getting anyone to hire me. So, he supported us, and worked upwards of 80 hours a week until our son was 3 months old when he found a steady job with less hours (more like 50–60)—so this was amazing for both of us!
Then he was laid off. We were owed a lot of money from the employer and he never pulled through. It was very difficult for us financially, and very emotionally draining on us both. I was in school and got a part time job to help as much as I could. He eventually got two new jobs to try to compensate for the lost income..yet that meant traveling between two jobs and we never saw each other. :(
Then, unfortunately, at the end of a day shift going into night…he is told the place has been sold and we are yet again left with nothing. So, three times in less than 4 years he has lost his job unexpectedly and we have never made enough to be able to save, so we’re left with not having enough money for rent and food.
We always pull through and I have never made him feel badly for this. But, it has always been very upsetting that he now chooses to work so much. He will constantly be on the phone doing work, working any shift he can, ignoring family at home because work preoccupies his mind. If he isn’t working, then he’s sleeping because he doesn’t get much sleep at night (gets home late).

In December, it came to a crashing halt when I told him he needs to be here more for his family, and that money isn’t everything. He has a steady job, decent pay, we’re actually saving because we moved into my parents house and pay half the rent we were paying before. We are doing fine, and have a cushion which we’ve never had before. It feels great.

I have had this problem where he chooses work over family way too much. We have been communicating a lot because I’ve been expressing my feelings more openly and better since I’m not attacking him (I find writing all out and giving it to him as a letter to be best, so I can gather my thoughts).
He informed me yesterday, that he is not a workaholic (as I have accused him of being). He tells me he is very insecure. He is scared of not being able to support him family, and having the rug ripped out from under him. He says he can’t stop thinking about the money he is missing out on, when he has days off of work, and when he’s not at work he thinks about work because of these fears.
I had no clue he was that scared. I know I should have known, since of course it’s been terrible for me when he loses a job…but I guess since it’s not me being the one losing the job, that I could brush off the personal feelings easier.
I don’t know what to say. He knows I love him and if we can get through all this, I know we can always work our way through anything. I don’t want him to suffer or be that insecure. It can’t be healthy to obsess over something like that, right? How can I let him know that it’s going to be okay?
We have a game plan. We’re young and have time to work on our plan, we keep our eye on the prize and knowing that the other is always there by our side has made this possible. As hard as it has been, with school and work and having kids…it’ll all pay off. I have faith that it will, and I’m glad I get to go through it all with my best friend. He knows he’s my best friend and that we love each other.

So, what can I do to help him through this? How can I let him worry less? I know us having a second child is probably making the issue worse (he’s the money worry wart), so I don’t even know what words of comfort or advice I can give him. Any advice?