Your character is trained

Personality is not a locked prison. There is temperament, history, and limits, yes; but there are also habits that can be acquired through repeated acts. If you always say 'that's just how I am,' you may be giving up too soon on growing. God's grace and daily effort allow you to form a more patient, strong, honest, and helpful character. This is not about becoming rigid, but about gaining freedom. When the will is not trained, it depends too much on the surroundings, on tiredness, or on mood. Small acts, repeated with patience, gradually make it easier to choose the good.