Two and a half years ago my husband was working out of state and I ended up chatting on line with a former high school boyfriend on FaceBook. ( I know, I know) At any rate, they were “flirty” in nature. My husband hacked into my facebook and copied the few messages/chats he could find. Also there was a visit to my hometown to hang out with girlfriends. My one friend has a brother I dated 25 years ago and I gave him a smooch, which my friend, (his sister) took a picture of. My husband also logged onto my computer and has a copy of that. We had separated briefly during this timeframe. I know this all sound horrible, as for my character, but I have been married faithfully for 21 years with the exception to those two instances. After that rough patch in our marriage, we tried to piece things back together. Nothing else happend after we "got back together. Now I am definitely ready to leave this marriage and he is threatening me with that “evidence”. How badly will those things hurt me as I am a dependant spouse??? Super worried he’s going to screw me over silly nonsense. 
He also opens my mail and my email without permission using my computer. Loosing my mind!
He can allege adultery, using those items as evidence, to bar your claim for alimony. However, condonation (forgiveness) is a defense to an ascertation of a bar to alimony based on adultery. Marital relations alone do not necessarily constitute forgiveness, the court would have to make a determination of whether the affair was condoned after considering all the facts presented. Based off of the facts presented, I believe you would likely still be able to claim alimony.