Devils on my shoulders

how could i have doubt on someone who love me with all her heart for all these years? how could one guy change all my believe-system and make me a paranoia. I look myself in the mirror and i can see two devils on my shoulders, not angel. Whispering, casting all the jelousy, hatred and doubt upon my heart, inside my head. So i sit on this prayer mat, holding my two hands together and pray to HIM.