Being an Inspiration to Others

How can I be an inspiration to others if I can't even be an inspiration to myself at the moment? I feel hopeless and drained. I can't believe I lost custody of my beautiful angels to a substance abuser. How is that even possible? I don't have a track record. I've never been a bad mother. Why is this happening? All I've tried to do was better my life for my children and I get the short end of the stick. He hides his money, he works under the table, there are no paper trails... hmmmmm... We've shared joint custody, suddenly he wants to get married and his fiance wants me out of the picture. So, he listens to her, nevermind the children... the children need both parents, not just him. She's not their biological mother. She can't love them the way I do. I could care less what he does with his life, but when it comes to my children's lives and they are affected negatively by this outcome then we have a problem.