Hey, hey, that doesn't sound right. Is it the evil of monotony and boredom that plagues you? Things losing appeal is definitely not right. Maybe a little talk can lighten your mind? Say, what do you like to do the most?
I only have very minor depression issues, but at least for me, it helps to celerate the small things. Anything and everything you do while fighting depression is a victory and should be celebrated. Did you doodle something? Celebrate it! Made luch? Celebrate it! Nothing is too small.
This might help as well. My wfe suffers from major depression (diagnosed with mood disorders) and I asked her what she would consider the best/most important advice she could offer when dealing with depression is to talk about it with someone. I don't know if you feel comfortable doing so with someone on the internet or not, but I can make myself available if you like.
This sounds bad. Out of my personal experience, please do not see this as a destiny or something you have to endure hoping for it to change to the better by itself. If you have the chance and possibility, get rid of responsibilities that stress you out in your daily life and seek help to be able to enjoy things again. Life is beautiful but it's hard if not impossible to see if you feel like falling into a black hole. I wish you the best!