How do u deal with break up?

like i am a guy now i really really loved this girl like i can say she meant to me to such an extent that for her happiness i was even ready to give my life.though some misunderstanding she stopped talking to me and later got married.i am happy if she is happy in her life.but she never even told me she was getting married like i feel so sad that for the person i used to think so deeply she didnt even felt to atleast inform he about her lifes most imp decision.now the problem is i feel scared to fall in any relationship.i feel that if this happens again i will be completely shattered.most of the time i prefer to stay alone.i dont know what to do in rest of my life insted i feel just to work hard to such an extent that i can kill my loneliness.