How do you maintain dignity after a hurtful unfair breakup? Depressed and desperate...?

[Paris]

he broke up with me with a text..not giving a reason,, i was devestated and tried to reach him sevral times to find out what happened and why he did this to me.. he simply ignored all my messages, calls, emails,, texts..etc...Now i am hearing that he has started talking behind my back to those who I never approved as a friend. I'm so angry and hurt for what he's been doing to me..I loved this man so much and i always had respect for him that's why it hurts me so much...im very depressed...he is on facebook pretty active like nothing has happened.. i dont know why he would do this to me,

I feel horrible for begging him to give me n answer and he ignored me..i made myself look desperate..now i want to know how i can maintain my dignity and respect after him treating me like garbage..., i am trying to move on because i dont think that i would ever want to go back to him again even though i still have strong feelings for him.. im hurt so much ... what should i do/....need your help