Is it wrong for a agnostic to wear a cross?

I was raised Catholic and Baptist. And I grew up in a very religious home when I turned into a teenager all of these tramtic things started to happen to me. I think that God has abandoned me and doesn't like me, if he truely exsist why didn't he save me that day? p[art of me wants to get away from my minster family and a nother part of me wants to wear my cross and recite the "Lord's Prayer" I was wearing my rosery the other day and this girl yanked it off and said "this doesn't belong to heathens and s of the devil" I slapped the girl and got in trouble at school.That Rosery was very special to me, it was from my grandmothers and she gave it to me when I was born. It had red beads and it had a golden cross with red rubies in it. My mom put it back together and fixed it for me.