It sounds to me as if you and your son are all suffering--not so sure it's because of you, though, bumble2u. You're a stay-at-home mom, no transportation except taxi, a single parent (practically speaking), with a husband who aids in overwhelming you with life.
As you say, he's gone till late. "I have tried to decompress, but my H when he comes home has an agenda for everyone, every little thing calculated and evaluated. I can't breathe." Well, no wonder. Your sons feel the stress from this man as well, I suspect--and are struggling accordingly.
You aren't the source of the problem here, bumble2u. I hope you can get counseling ... or post enough here to discover that you would only make you sons' life's much worse by leaving them to this poorly functioning (and probably very unhappy) man. Add to that abandonment by their mother (how they would perceive it--and blame themselves most likel), and your leaving only makes everything worse for everyone.

Please--get counseling, or stay online here and keep posting until you connect with someone who can relate ans who me young eel a connection with. Talk it out ... everything ... insist that your husband get help through his just insurance. If you must leave, but sure it's as a family--with your sons. Involve them, let them acknowledge their feelings. They must be torn, confused, and angry.

This is a good palace to be. Please use the resource available here, bumble2u. There are good, generous folks here who have been through what you're going through. Hang un.
Roadie