It is easier to disbelieve everything then to prove it. Putting in the time and effort, others only what you have done in front of their eyes. No matter how much work and effort you have put in, other people including your family wont get it. They haven't ever been where you are at, nor put in the work you have. Having the courage to believe in yourself is all you need.
The main fact is, develop your mission to serve your right target audience and talk to your right clients.Those are the ones you matter the most. The people who tell you, this or that will never happen is showing their personal views, not reality.Those who talk down to you are normally the ones who are you not your clients and aren't going to pay your bills with nor give the long lasting support you need to grow your business. You mission is where it all starts from. It is who you are.