Some of this sounds familiar to me. Is there any chance that husband would join you in marriage counseling? (my dex refused-why can't "I" just change-LOL).
You need do something for you. If you want to go back to school, you should. I think it would be a good idea to talk it over with husband, explain why it's important to you and get his support. The reason why I say this is that it doesn't sound like he is helping out at all now-and you are really going to want him to if you go back to school. I went back to school too. In fact, I am still trying to finish an associate degree (slowly but surely, I'll get there)It was a wise choice for me but it did add additional stress.
If husband doesn't help you out, you will find that you are spending time in class (its good to be out and with other adults though)having your own homework deadlines to meet, and running the house. I am not trying to be negative. I'm glad I went back to school, it's taken me years to get this far (5 classes away)but I was able to get a fairly decent job based on the skills that I learned.
I can usually only manage one class a semester because I'm single, work full-time, and issues with difficult child. I'm also anal when it comes to assignments-if I can't give it 110% I don't want to do it. Right now, I am trying to take the internet classes for the convenience (but it might be good for you to get out of the house for awhile-even if it's part-time).
Good luck. I hope you find some solutions that make you happy.