Let myself be myself

i want to learn to be myself agian iv been with a girl for the past four years and she has let me down all the way i got sucked into so called love and now i all i think about is what she is doing we live together but it just feels like were just house mates we now have a little girl and i want her to know who i am not what my girlfriend has made me a “complete arsehole” she has destroyed my true self and i want it back.