Frustration with the other parent.
Sometimes it just drives me crazy that I am the only responsible parent. I cannot even begin to imagine the life his father lives. How can you not just watch him sleeping at night? How can you not be so proud when he comes home from school every day? How can you spend a single day away from him? I don't know what I was thinking when I got together with him, but man am I happy for my son. I have no problem being MomDad to my son. I just wish I didn't have to work so hard so I would be able to enjoy him more.
I spent a long time being VERY mad about it, to be honest. But now I look at this wonderful young lady and realize how blessed I truly am and how much he has missed out on. He chose to run away and no amount of half assed (excuse the cuss) attempts to be a father at this point are even an interest to her. She's a beautiful person in spite of his neglect and your little one will be too.