First, I would like to say that I’m sorry that you are going through this.
I do not know that you would want to pursue alienation of affection. From what I have read it is expensive and difficult to prove. You must show that you had a viable marriage and that this person alienated your spouse’s affections. This does not necessarily have to be a “lover”.
Adultery or criminal conversation is having sex with someone other than your spouse and though it is rarely prosecuted it is illegal in NC. This goes for even during separation, I believe unless express permission is given by the spouse.
I’m not certain what the exact steps are for filing a claim for alimony. If either spouse makes more than the other, that spouse can file for alimony unless there is marital misconduct on the part of the filing spouse. Meaning that if you have an affair, you forfeit your right to alimony.
I suggest that you get to an attorney as soon as you can. Gather as much information as you can, receipts, phone records, record a conversation between you two where you specifically ask if he’s been unfaithful if necessary. Since he has not admitted to the affair your actions could not be considered condoning…condoning/forgiving would mean that you continued to have sex with him after having knowledge of the affair.
Get a separation agreement drawn up. This will protect against abandonment. One party must leave the marital residence before separation can begin so it’s useless to attempt to claim abandonment if your spouse leaves and is taking care of finacial and other obligations, such as child support.
I have a friend in a similar situation. Her husband cheated on her but manipulated the situation so that it was her wanting to leave. She knew nothing about the affair until the week after she signed an agreement. I think she is going to attempt to have some of it reversed, he did not disclose all their finacial information, but I’m not sure that this will work…