I really enjoyed mat leave. I joined a playgroup when he was 4 months old, I went for me not ds and I loved it, I needed some adult conversation. You can join at any age, I think ds enjoyed getting out and seeing new things too. I can't get back into playgroup at the moment (it's full) and I really miss it!
I also had a lot of friends on mat leave at the same time so we caught up a lot at each other's places, we would take it in turns. I went to the pool for baby time most weeks too and occasionally I would take him to the library as well. I also joined a mums exercise group for a bit when he was 9 months too. I was out of the house most days. I also also cooked a lot and experimented a bit with meals. My house was also pretty clean most of the time 😂
I went to full time work when ds was 14 months (after a brief stint of returning to Uni when he was 10 months). I've just dropped back to 4 days and DS (almost 2 now) is just starting his toddler tantrums which is hard! I occasionally wish I could go back to that happy 6 month old easy baby haha! I def could not be a SAHM full time past 18 months I think!