Husband left me 6 months pregnant, he is in the army, what do I need to file desertion?

I am now 32wks pregnant, at 6 months my husband who is in the army left me for another woman.., moved in with her and everything. (she as well is in the army) He has made it very hard for me to file for adultery against him. He hasnt paid me any spousal support, and has only shown up to one of the doctors appointments since he has taken his "time apart." He refuses to talk about divorce and continues to claim his money is messed up. But has taken three trips with this woman (who knows me and knew we were married and having our first) and right now is out of state with her meeting her family. I need to know what information do I need to provide to get him on desertion.., since he up and kicked me out of my own house and now I live with my mother and sister in a two roomed house, with nothing to my name, not even my own bed, or room. Ive been trying to give him the chance to change.., I was raised old school with marriage.., but it seems like he doesnt value the vows we took and has taken the easy road out.., Please I need advice.., If you have rude comments because I know how sometimes people can say mean things, save it., I really just need advice. Thank you