Alone in a crowded room

A huge feeling of loneliness just slapped me in the face. I'm sitting here smoking on the porch with my best friend, but I feel so freaking alone. I have no idea why. I hate this feeling. Sometimes I feel like I suck everything out of all the people who support me. I feel like I constantly go to them for advice and I get on their nerves. I don't mean to bother them, but sometimes I just need to talk. Let it out, vent. Ya know?