Why Wasn't My Ex A Better Father?

Only five years ago, only a young preteen at the time, our daughter sat, and waited. Daddy called her and told her that he would be on his way to pick her up within 1 hour. She was so anxious that even if she had other plans, she would cancel them for a chance to go out with her dad. And so she got ready, and waited patiently. An hour slowly ticked by and still no sight of daddy. She called him and he told her "I will be right there, my baby"....she waited in the chair that sat right by the front door window so she could look out and see him coming down the road in his new, beige toyota wagon. Still after waiting ever so patiently, there's no daddy coming down the street to pick her up. Where was he? Why didn't he call? She picked up the phone and dialed his number, and only got his answering machine. She left messages, she texted him and wondered where he was. After sitting for hours upon hours it seemed like she had waited way too long...and daddy never came. Tears came flowing down and I cried like a baby for her, but didn't want her to see my tears so I had to stay calm. Why did he do this to her? It happened over and over and over again. Then one day, she starting realizing that he was only telling her tales and that he was not going to come. She gave up on him, and is now not even caring whether he calls or comes or not. It has been five years now......, she has grown to know the man that he is, and it's a shame. I wanted so much for her to have her daddy, but he was just too busy. I don't understand how a father could do this to his child. Our daughter is nearly 17 years old now, and growing into such a beautiful young lady. I have always been there for her and she knows how much she is loved....but I will never understand how a father can just dump his daughter, because he is so involved with another woman. I know that her heart will heal one day and she can look back and see that I have always been there for her.......what happened to my ex? I just don't know.