career/ money.
Had to give mine up when I left abusive exh, wasn't compatible with lone parenting. Had a few months of income support when maternity ran out, topped up by some casual work I could take dd along to.
Did a ft degree for alternative career, continued casual work alongside. Once degree done and dd at school did various shitty jobs till an opening came up in my field.
Dd is now 14, career ok but still limited. Promotions I'm eligible for would require being more flexible on time than I can be right now, or will be till she's 18.
Hobbies- again had to give up, too expensive and not compatible with lone parenting. Lucky in a way that my career and hobby were in the same area, so my casual job allowed me to do it to some degree. Unlucky in that it served to remind me what I'd lost.
Friends- had childhood bf still, but not nearby. Again lucky in that I had some social interaction around job, unlucky because I resented some of those in a position to do it as a hobby, either because they didn't appreciate how lucky they were from my PoV. Or because they were pretty shit at it despite money but still able to do it when I couldn't, despite the fact I could beat them blindfolded.
Made some friends at playgroups, nursery pick ups, uni etc, but more casual than anyone I'd ask for help. One single parent mum I became close to after a mutual offloading of how annoying we found it when certain sahms with partners and decent incomes talked about how hard their lives were. We became and still are close, and shared lots of childcare, emergency support etc.
Health/exercise.
Again tied in with casual job. I've always been sporty, plus exercise and sport were my go to stress relief and escape throughout childhood. I did loads of walking, not least to reduce fuel costs. Also did some shitty exercise videos I got from car boots or charity shops. I don't even like aerobics, and didn't want to lose weight but beat sitting down every (long) evening. Plus sometimes I needed the adrenaline buzz if I felt low.
Love life
None existent initially. Then even when I did meet anyone, I wasn't prepared to leave dd regularly in the evenings. Might have thought differently if I'd been home in the day.
With hindsight it hasn't really changed anything since dd was 5/6. Given I don't do introducing dd to people, it just meant I ended relationships that wouldn't last earlier than I would if I didn't have a child at home. Tbh though I've always been the type who is happy single unless someone is adding to my life, rather than being someone who needs a partner and hates being single, might be harder as a lone parent in that latter group.
Even without pnd, it does seem at times in the early days that life will always be this way, but I promise you it isn't. I remember envying people who could go put their shoes on and go to the corner shop rather than it being an excursion.