I agree with the pp that going back to toddler wrangling is very hard after such a long gap.
I hope this doesn’t sound too harsh but nothing is going to change unless you put the effort in op; something which feels virtually impossible for you atm; so is this really a question of you being in a rut, or, is the real question that you feel too depressed to change things? Maybe you need to talk to the gp?
From what you have written above, you have EOW when you “just” have the toddler, and although toddlers can be relentless, surely it would be possible for your dh to look after them one regular morning, afternoon or evening during that we, so that you could pursue an interest?
And I think you should go out with your dh once a fortnight too. You say you have no childcare help, but why not employ a baby-sitter? An energetic grandmother type who lives nearby? Ask for recommendations from everyone you know. Get talking to other parents at the school gate, at the local playground, ask on class WhatsApp etc. And just go for a drive or a walk or meal with your dh , maybe try exercising together, learn a new hobby together, and try and revitalise your relationship a bit?
Or is your relationship what lies at the bottom of all of this do you think? Is your dh’s passivity getting you down? If so, would counselling help?
Good luck with getting to grips with what is wrong precisely op and in taking some action dependent on your conclusions.