I've been extremely depressed and been having existential problems lately

so lately I've just been feeling like I'm not part of life anymore, I barely go out lately because of the weather and it's been super hard to get out, I have a much smaller friend circle than I used to and I play video games to try and meet people online but I haven't even been motivated enough to do that lately and I just turned 29 and I feel like this is the rest or my life and I don't have a real purpose, is this just a phase a lot of people go through or what's wrong with me?