Why did this man do this to me?

A guy that I have been getting to know since May came over the other night excited because I helped him to get a job in my building. We were talking, he was pinching my cheeks, and asking me to come sit next to him. He asked me did I think that I could ever get to the point where I could be a stepmother again. A little while later, he just blurted out that he is expecting a baby with another woman in two months. The woman is living with him right now. He also said that he would never get married again but he wanted a child. He left a few minutes later like nothing had happened. Why did he pick this evening of all evenings to drop this bombshell?