What type of personality disorder/mental illness is this?

My mothers husband has got to have some kind of mental illness. He seems to have the inability to tell the truth about virtually everything. He has never had a job in his life. He is 70, and a trust fund baby. He spends money at an incredibly high rate, impulsively spending almost 500K of my mothers money in 7 years. It is impossible to have a conversation with him because he will not stop talking. The people that knew him during his younger years say that he always had on a suit and tie every time they saw him, yet he never had a job. He claimed to own a company, but noone has ever seen it. His ex wife divorced him 16 years ago, and he has never made an effort to see his 4 children since, nor payed one dime of child support. He has just recently been served with almost 400K in back child support, and has no way to pay it. My mother is now broke, and has 100K in unpaid income tax because of the money he withdrew, and it seems to have absolutely no effect on him. His entire story about his past seems to be one big fabrication, with grandiose stories, yet no verification that any of them are true. He appears to like to socialize, even though he is socially hopeless, and also appears to care about my well being, and my sisters', despite financially demolishing my mother. He seems to find humor in tragedy. For example, I caught him watching YouTube videos of the Reno air show crash, and laughing. But when he is around my mother, he seems to be so kind, and appears to be so compassionate. He spent 40K on attorneys trying to defend himself for the child support case, then just stopped contacting his attorney, who eventually withdrew from counsel, missed his court date, and now has a bench warrant. Yet, he seems to be completely unaffected by it, like it doesn't exist. He has never been violent. What in the world is going on with this guy???