My husband is a half ass partner and father

I am a stay at home mom and my husband is a soldier. We have a toddler and a newborn. In our 3 1/2 years of marriage one of our main issues is he doesn’t do his part with the house or kids. Today he planned on going to the gym after work. He just called me on his way home from work saying he’s too tired but he’s going to come home and take care of some things that he needs to get done like post stuff on eBay and organize paperwork. He told me not to bother him or ask him for too much. I said so you’re referring to the kids? He said yeah don’t keep asking me for help. I got upset and told him he needs to be a father when he gets home. He said I could be going to the gym right now but I am not. Do you want me to turn around and go to the gym ? He always says stuff like this. I’m sick of it.