How do I deal with these feelings?

My husband works a lot. Sometimes 14 days in a row without a break. I stay at home with my 4 year old who has ADHD, SPD, and Autism, as well as my NT 2 year old. My days are incredibly long, exhausting, and isolating as we live in a small town and I live 500 miles away from family due to my husband’s job. I used to be a teacher but had to give that up due to childcare costs and my oldest son’s unique needs. Needless to say, the longest break I get is at nights when I take a shower and my husband watches them for 30 minutes. On his days off, he tends to the garden, yard, house repairs, runs errands, etc. He never wants to stay with the kids and let me do anything because our autistic child doesn’t like him (we are working on that) and doesn’t trust him. My husband is gone a lot for his work (military) and that is why he doesn’t trust him much. But my husband also is not very good or patient with him, although I know he loves him. I’m burning out and feeling so resentful of my husband though. He’s been working out in the garden for the past 4 hours in 100 degree heat and I’m jealous of that because he’s alone and not being bothered. I’d rather do it. I’ve tried but my son just screams for me at the window and my husband has zero clue how to calm him down and just yells at him or ignores him. No matter what I do I can’t get my husband to do anything other than financially provide and “babysit” while I shower or go to the doctor. He doesn’t take much more of a role than that. I know he loves them but parenting is like a foreign concept to him. My burnout is so severe though that I’m honestly thinking about divorce so I could move back home and have the help of my family and parents. I feel so lost and alone. He tells me we cannot afford childcare or preschool. He doesn’t start kindergarten until fall 2023. 😞