I’m not in the same situation as you. But mine is 2 1/2 and it’s been just us for most of her life…. seeing dad daytimes (sporadic) from 11months to 18months, for almost a year I have work 21 hours a week and apart from work have no down time at all….a lie, one night over the last year, but I had to come home and parent after a night out.
it is hard and sometimes I resent the parent that is doing whatever he likes, when he likes!! Especially on those god awful days that never seem to end, with tantrums and pure hell 😉 but then I remember how much he’s missing!
what I do is try and include her in my old activities (although always shorter lived) walk the dog in the beach, go to the pub she has crisps and I have a beer, go for breakfast…. sometimes it is an epic fail! With tantrums galore and I wish the ground would swallow me up and I revert to that feeling if resenting the parent that walked away, but at least I feel like I’m getting out there and being me, even if it is for 30minutes, every now and then.