Why do I feel severely depressed?

Hello, I’m new here. I was if there was anybody that ever been through or knew someone that successfully got through being depressed ALL THE TIME? My whole life from childhood to now (26 yrs) has been pretty much trash. I’ve never really been able to maintain friends or even consider some of my family as friends. The 2 things I heard for my whole life are fat and ugly. Even when I lost weight, I’m still called ugly. Never even had an opportunity to have a girlfriend, let alone sex. Now I’m not so big on having sex, but a girlfriend at least. I’m in the military and I haven’t even been able to bring myself to go home to visit for 5 years because I fear that like the other times, I’d go home on vacation just to have friends and family be too busy for me to visit and I end up sitting at my moms place watching anime because even my mom is too busy working or going to church. The people at 2 different churches judge me like anybody else too, so I have a complex about going to church to worship only to be called fat and ugly there too. Top it all off, As soon as I started going to the gym and lifting weights and building SOME esteem, I got diagnosed with Diabetes. I’ve also recently went through a “unknown” complications at work because people decided that they wanted to include my name in something and get me ostracized by my sergeants. I have no one I can talk to hear because I’m 26 and all the rest of the people in my unit are young party fools. I cant talk to my sergeants because they’d go tell everybody. My family either blatantly ignores me or gives me the “um-hm” response. I’m really done, it’s building too much inside. The only solstice is when I play video games. I’m not having any thoughts on “killing” myself, but I always think about why I’m living if its for loneliness and pain.