I'm going to echo Ahardyfellow and Auster, but put it here so it hits your inbox.
It sounds like you are struggling with connections and novelty. Be active and ping your friend network, see who is up for doing new things with you: find a new restaurant and catch up, go to an active collaborative activity like an escape room, etc. Push yourself a few times and it will build momentum and keep you all connected.
If your friends aren't up for these things, find new friends (and keep the old, you can have more than one friend group and they don't have to interact).
I'm an introvert and leech off my wife's friend group so I'm not the expert on making new friends, but I think Auster's idea is solid: Find a hobby that gets you out of the house and talk to people doing the same thing. Plan to see each interaction as a success, even if it doesn't make you a new friend or even go well. The goal is to socialize, and if you do that enough, you will find people who make you happier.
Novelty is a big factor in our happiness that doesn't seem to be talked about much. If you are always following the same routine, try and shake it up. It's not comfortable at the start if you've been in a rut, but it will make you happier. Put it on your calendar to do something new. Even if it's only once a month, and the 'newness' is just doing something you like in a different place. Again, it's momentum, and more challenging new things will seem less daunting over time.
Passive aggressive 'All your veggies are actually fruits' energy here. I love it :)
This has been a regular debate in my household and I'm with you on this.