What's it like to be a best mate? any advice? x?

I was best mate with a girl called amy and she thought i was being funi with her and quiet, I was going through some trouble with a guy i was with for nearly 1 month and he left me. Later on throughout the week amy started ditching me then got a girl o thepone and started threatening me. i know it sounds pathetic and childish but i just want someone to hang with now and again, i have my mum but what shall i do , i am alsways moping aound the house and i wnat to get out more help please x