I'm starting to realise the same. A lot of my activities I used to share with friends/family and I've got to start enjoying them for myself. Watch a movie, just enjoy it on your own. Made some new art or music, appreciate the journey and what you've done for yourself. Sounds like you got out there though and were able to experience some good things. Nature is amazing and I'll push myself some more to get some fresh air and sights.
you (we all ) need some "me time".
i've never really suffered depression, so it's a little difficult to properly relate to the experiences of others.
but "me time". - every so often - perhaps every 2nd or 3rd week i take a drive - on my own.
i go wherever the mood takes me, travel at whatever speed i please, play whatever music i feel like and stop wherever for as long as i may please.
not having a passenger / company is bliss - somewhat self indulgent - nobody else to consider at all, not even for a nanosecond.
one of my more interesting drives started out as a intended short one - from bantry bay to simonstown.
i landed up continuing on - all the way to cape point, circling back via scarborough / noordhoek / chapman's peak / hout bay.
was a hot day , stopped at every mac donalds i saw for a mcflurry (landed up having 5 in total).
was a good day.
or also on a bike (bmw dakar - on / off road kinda bike), go exploring off the tar road and into the hills (silvermine area is a favorite, or thru tokai forest)
another habit is to switch off - like i did for the last 3 days - phone turned off (unless i need to make a call), intercom off - near zero communication with anyone - just staying home, playing music and doing whatever.
it's refreshing. !!