I lived with my ex for almost two years and if i had the chance to go back, I would probably opt to live alone. Now I live alone and it's great
but in your situation specifically I would probably see a doctor to make sure you're not depressed. You have a ton of support here, so make sure you take advantage of it. Whenever i'm feeling all lonely and wanting to talk I just browse the forums and feel much better when i'm done. It's hard to feel alone when you have such a close-knit group of people willing to share pretty much anything under the sun.