What am I suffering from

I feel shame,lonliness,isolation, sadness and guilt every day, to varying degrees. I feel really guilty about my emotions and the things. I feel like I have lost all purpose in life. The only thing that keeps me going is my friends. And I've been a colossal idiot about it. I didn’t seize the moments I had. I let them slip away, wasting my time on things that didn’t matter. I'm full of regrets. Life feels like a prison to me. Loneliness is one of my greatest fears and I can't figure out how to not be truly alone.