Leah, I just Googled "is Alabama a no fault divorce state" and there were some interesting articles, apparently Alabama has provisions for "no fault" divorce AND "fault-based". So in your case, the answer depends on which type of D you're going for. Adultery in a fault-based state can be considered and at the judge's discretion may affect the alimony amount. So it's definitely something you want to talk to your L about.
Also you asked if having sex with your H would affect the judge's decision, yes it very well could. Your's H's lawyer could argue that you "didn't care" about the affair because you continued to have sex with him, so if his affair was so harmful to you, why would you do that?" So tread carefully there!
