Fighting for his attention!?

For the last couple months my husband has really changed, he focuses all of his free time researching and working of his truck, he has stopped caring about the things at home that he used to care about such as his other hobbies and responsibilities. When I try to talk to him its like he is in a fog and isn't really listening to anything I say. His total focus is his o.c.d. like behavior about his truck! And when you do get his attention,he always has the "what have you done for me" attitude. When he does talk if I try to add my 2 cents into a conversation before he is finished speaking he will fly off the handle and scream at me to let him finish what he is saying first. I basically shut down at that point because I don't intend to make him upset. When if ever we do go out to dinner as a family or with others, I will show affection by placing my hand upon his knee or lean into him, but he does not acknowledge me at all. He will even go as far as saying something criticizing or rude to me, and I become so embarred I again just shut down and say nothing. His mood swings have become very irrational and when I mention anything about it he just ignores me. We have a 5 year old daughter that has really become daddy's little girl, and refuses to listen to me anymore without first consulting her father. He will undermine me when I try to discipline our children and in doing so I have lost all control of our two younger children. I have managed to get him to sit down with me for a few minutes and explained that we don't seem to have anything in common anymore and I miss him. I really want to try to find our way back to communication. He is not a bad person, as a matter of fact he really is a tender heart person, but he just really seems to be lacking in the department of empathy. I get so jealous of all our friends that are in relationships because their spouses seem to be in tune with them, they show affection, go out of their ways to do even the smallest things for them, and are romantic in some way or another. What's even worse is when I try to brag about my husband to my friends its along the lines, as he is a good dad, a good provider, I know he loves me...that is it! I know I shouldn't complain because when I think about it he is a good husband and dad, he does do a lot of house chores, cooks dinner, and helps see that our children off to school...among a list of other things. I am just not sure how to approach subjects anymore and I would like to find something we can talk about without it only being a 2 min. conversation. I know all these problems are not all him, that I have much to do with it as well, I just need to find my way back to good communication and a good husband & wife, and parenting relationship with my spouse.