Thanks for bringing your question to JustAnswer..
You have written an almost textbook description of someone with Asperger's, so I think it is worthwhile trying to have him evaluated. Here's a description, from the Interactive Autism Network, of how a person can seem during courtship, and it explains a lot about why you may not have recognized it earlier:
Men with Asperger's syndrome have many qualities that can be attractive to a prospective partner. 6 When conducting relationship counseling with one or both partners having the characteristics or diagnosis of Asperger's syndrome, I often ask the typical partner, ‘What were the qualities that made your partner attractive when you first met him/her?' Many women describe their first impressions of their partner with Asperger's syndrome as being someone who is kind, attentive, and socially or emotionally immature. The term "silent, handsome stranger" can be used to describe someone who seems relatively quiet and good looking. Physical characteristics and attentiveness can be important, especially if the woman has doubts regarding her own self-esteem and physical attractiveness. The man's lack of social and conversational skills can lead to his being perceived as the "silent stranger" whose social naivety and immaturity can be transformed by a partner who is a natural expert on empathy, socializing, and conversation.
I have noted that many of the partners of men with Asperger's syndrome have been at the other end of the social and empathy continuum. They are intuitive experts in understanding and empathizing with someone else's perspective. They are naturally gifted in the ability to understand the world as experienced by the person with Asperger's syndrome.. They are understanding and sympathetic, and they provide guidance for their partner in social situations. Indeed, these are the characteristics that an adult with Asperger's syndrome recognizes that he or she needs and would find desirable in a partner. He or she will actively seek a partner with intuitive social knowledge who can be a social interpreter, is naturally nurturing, is socially able, and is maternal. However, while a socially insightful and empathic partner may understand the perspective of the person with Asperger's syndrome, the person with Asperger's syndrome has considerable difficulty understanding the perspective of his or her typical partner.
The attractiveness of a person with Asperger's syndrome in a prospective relationship can be enhanced by intellectual ability, career prospects, and degree of attentiveness during courtship. Sometimes, however, this attentiveness could be perceived by others as almost obsessive, and the words and actions appear to have been learned from watching Hollywood romantic movies. The person can be admired for speaking his mind, even if the comments may be perceived as offensive by others, due to his strong sense of social justice and clear moral beliefs. The fact that he may not be "macho" or wish to spend time with other men at sporting events or drinking alcohol also can be appealing for some women. The person with Asperger's syndrome can be a late developer in terms of relationship experiences, which also can be an attractive feature. There may be no previous relationship "baggage." I also have had many women describe to me how their partner with Asperger's syndrome resembled their father. Having a parent with the signs of Asperger's syndrome may have contributed to their choice of partner as an adult.
If this sounds familiar, you can find information about how to communicate with your husband, and advice from others who have walked this path. The important thing to remember is that if he indeed has Asperger's, there is no malice in his self-absorption--it is the nature of the disorder.
You might want to try using some of the communication techniques that others have found to help before deciding on a divorce, especially since you have a young child.
Here are some links to resources:
A good article on diagnosis :http://www.help4aspergers.com/pb/wp_b79de52e/wp_b79de52e.html
A book for women in relationship with a man with Aspergers (you'll see them called "Aspie's ")
And the title of this book seems to sum up how you're feeling right now: Alone Together
Since it will most likely be impossible to convince him to go for an evaluation, since he sees nothing wrong in his behavior, you have nothing to lose by educating yourself about how to communicate with an Aspie, trying the techniques, and seeing if that helps get your needs met. If not, at least you will know you tried everything before giving up on the marriage.
I wish you all the best,