When I feel aggrieved, when I have been let down by somebody, when somebody doubts my ability, I find myself thinking, 'I'll show them. One day they will be envious, wish they had never doubted me. I'm going to do something amazing.'
Three thoughts come to my mind soon after this:
1) By the time I do get to wherever I am going, they are probably not going to care or even know who I am
2) By the time I get to where I am going, I am not going to care or know who they are
3) If I start doing things just to prove people wrong, I am in all likelihood going to start working on things that are not quite right for me
So I let those who doubt me, give up on me, move on from me do so as their decision. It has no bearing on me and what I am doing. What I am doing comes from a place within, and I do it to meet a deep desire from that place; to bring into the world that thing which only I can bring; to experience that moment of bliss that only comes when I know I have followed my path.