The brief relief of seeing other people when I leave my room...

The brief relief of seeing other people when I leave my room turns into a desperate need to be alone, and then being alone turns into a terrible fear that I will have no friends, I will be alone in this world and in my life. I will eventually be so crazy from this black wave, which seems to be taking over my head with increasing frequency, that one day I will just kill myself, not for any great, thoughtful existential reasons, but because I need immediate relief.