Hi K.,
How wonderful that your two children will be so close in age. My three are each eight years apart (27, 18 and 4)! Your son will have a playmate and close sibling always :-)
What the other posts said here are right about arranging certain 'tasks' ahead of time - especially before your new baby comes along.
My husband works really hard physical labor (often long hours) and when he comes home he needs shower - food - couch and just cannot focus on anything else. I try to be understanding about that, some days he is just really exhausted. So I also felt guilty asking for help (for like a minute) ha ha. Seriously, he had to learn to get a second wind after resting for a short time after work and I had to learn to not jump on him before he had a chance to eat and rest. I could not do it all alone - no one should have to.
When my daughter was a few months old, I remember handing her to him when he walked in the door and 'running away' upstairs and locking myself in my room or running out the door to meet a girlfriend for a drink. This was not healthy for any of us - but I do understand where you're coming from. The first time I did that, my husband looked at me with a frightened look and said, "what do you want me to do"? And I said - "be her daddy!" and ran - this was not the right way to handle things - please don't let yourself get to that point.
What worked for us was to talk at a time OTHER than when either of us was exhausted / overwhelmed (a narrow window). When the right time finally presented itself, I pointed out some exact things he could do that would go along with his schedule and then asked him "which of these things are you going to be taking over?" I didn't ask "if" I just went on the assumption that he was going to take some things on.
When our daughter was little I was up with her every night numerous times - she did not sleep through the night until she was 3!
We agreed I could reach over and pat his shoulder and he knew it was his 'turn' to get up with her without being mad about it - at the time that was huge for me. Also, he did the diaper changing on weekends. After he started doing just a few things, he really got the hang of it (it was his 1st baby and he felt a little incapable and I didn't realize that) as his confidence in caring for her increased, he began taking other things on voluntarily. I had to bite my tongue not to criticize the way he did things - my Mom pointed that out - she said "it's okay for dads to do things their own way", and she was so right.
Right now our routine is that each Saturday morning my husband takes our daughter (now 4) with him to run errands, he does all the grocery shopping and then they usually stop at the Park or somewhere else 'fun'. This gives me some time for myself. It's also his part to help her brush her teeth each night after I help with her bath, then he gets her into bed with a story picked out before I come up to read to her.
I was a single Mom with my other two and I truly appreciate whatever help he gives me, because even the littlest things make a huge difference. I let him know that I appreciate his help, even though I guess I don't have to - it makes him happy to hear it.
I was surprised how receptive my husband was to exact 'tasks', rather than me tearfully complaining "I need you to help more" - this was too vague and he didn't really know how to help.
I trust you'll sit down and think of a few particular things he could do within his schedule to make your life happier - and then don't ask IF ask WHICH ONES he will do.
cheers,
W.