What you are basically asking is if you can sue for alienation of affections. That cause of action was outlawed in 1957. That other guy had no duty toward you most likely. Your cause of action would be against your wife and that could be dealt with in the divorce action.
You need to immediately and privately consult with an attorney who practices in the area of civil litigation and family law. Do NOT post anything more online, and do not talk about this matter with anyone who is not your attorney: what you say or write can be used against you in court.
Document everything--names, dates, descriptions of incidents--and keep all documentary materials you receive (including medical reports).
No attorney-client relationship is established via AVVO.com. The material posted by Kyle J. Bristow, Esq., is for educational purposes for prospective clients only and people should not make legal decisions based on it. You are advised not to take, or refrain from taking, any action based on what Mr. Bristow has stated on this website.
Don't take it out on the guy your wife was sleeping with...it's her fault, not the guy's. Sue your wife. No, I know of no law or cause of action which would be a basis for civil litigation. Meanwhile, you are the presumed father at this point in time because she's conceived a child during your marriage. Make sure you hire an experienced family law attorney for the divorce, and don't try to represent yourself. This is an issue that must be properly handled in order to establish you are not the father.
Mr. Colman is licensed to practice law in Michigan. The response herein is not legal advice and does not create an attorney/client relationship. The response is in the form of legal education and is intended to provide general information about the matter within the question. Oftentimes the question does not include significant and important facts and timelines that, if known, could significantly change the reply and make it unsuitable. Mr. Colman strongly advises the questioner to confer with an attorney in your state in order to ensure proper advice is received.
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