You need to consult with a lawyer. You do not have to sign his waiver. However, if you are served, an answer needs to be filed so that he is unable to get a default judgment. If you want to prove adultery its not a bad idea to hire an investigator. However, what you find out may or may not have an impact on your divorce. It may only get you a divorce decree that evidences fault; each situation/case is different and community property is a big factor. Again, consult with a lawyer in your area.
The information provided is not advice but a legal perspective and you should schedule a consultation with the lawyer of your choice.
I'm sorry to hear about your husband's adultery.
Of course, I don't know the specific facts of your case and cannot say whether making the adultery an issue would even be worthwhile; it usually is not. I also don't know whether the picture, in and of itself, would actually prove adultery; actual textbook adultery is difficult to prove. I would recommend that you consult with a reputable family law attorney in your area as to what sort of case strategy he or she would have given your particular set of circumstances.
You are free to file an answer and/or counterpetition, but I would strongly urge you to discuss your case with an attorney before doing so, especially since you have not yet been formally served. An attorney can make sure that your husband has filed in the proper court and that his pleadings are proper and can advise you whether you should allege fault grounds (e.g., adultery), etc. based on your facts and whether you should request any sort of temporary orders.
I wasn't quite able to understand the situation with the waiver of service and his not "serving" you with the petition. If someone is going to sign a waiver, they are indicating that they do not want to be formally served with the petition, but they are still informally given a copy of the petition. If you decide not to sign the waiver, then the clock for your response doesn't start ticking until you are formally served. If you go ahead and file an answer or counterpetition, then you are short-circuiting the process and eliminating one of his necessary steps--which you may or may not want to do--another reason to discuss your case strategy with an attorney.
I hope that you discuss your case with an attorney, and I wish you the best.
The foregoing comments do not establish an attorney-client relationship and only reflect the opinion of the author, who does not have the benefit of a full understanding of your specific circumstances; they do not constitute specific legal advice. If you have a legal issue, it is best to consult with a reputable attorney in your area.
Your best move is to get an attorney who focuses on family law issues. They can accept service for you and decide whether you need to file a counter petition or just an answer. The adultery only matters when it comes to dividing the community property. Call us if we can help.
DISCLAIMER: This answer is for informational purposes only under the AVVO system, its terms and conditions. This answer does not establish an attorney client relationship. I am admitted only in Texas. I am not intending this to be legal advice, because I don't know the particulars of your situation. Call me if you would like to discuss this or other issues, 210.501.0880.
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