How can I tell if my spouse had sex with a prostitute?

I've been in this situation before and have some insight to share with you.  In my experience, he was lying and trying to cover it up. By pushing you to std testing, he's distracting you so he can shift the guilt he feels and blame it on you. In a guilty man's mind I believe he's thinking-

...if I cheated...you must have as well....but you're much worse than I because it's okay for me to cheat...but not you...now you're a cheating dirty slut...just like that prostitute 

Men believe they're entitled to treat women and children like property. Often they use intimidation and violence to control us.  

He'll never admit to cheating, he'll never apologize and he'll do it again and again. Truly they don't think it's a big deal, it's just their way of being social. They desperately want us to accept it, perhaps join in the act.

The fact that he has several versions of the story, could indicate the presence of deception concerning the events that occurred.If he expressed that he may have had contact with a prostitute, there may be a likelihood he may have had sex, but you cannot be 100 percent certain. The suspicion alone would appear to be a source of distress for you. Having the STD screening will certainly be helpful in terms of your health since it appears that he may have been involved in an indiscretion that may also be interpreted as a breach of trust between you.

The answer lies in what the outcome will be. How will things end if you find out he had sex with a prostitute? Will you leave? Will you try to work things out? 

The multiple versions are concerning. He seems unable to be truthful and this is damaging your relationship. 

Before considering marital therapy, please find a counselor for yourself. The right therapist can help you uncover what is right for you. 

The short answer is: you may never know.  The only person that really knows is him.  Here are some things to consider.  If you're asking this question, it may be an indicator of the health of the relationship itself.  It wouldn't be a waste of your time to try some relationship counseling.  I don't know where you are in your mind on the relationship, but couples counseling is not only for couples on the brink of separation.  Yes, it can help avoid separation, but it can also help work out issues exactly like you are asking about.  Even a healthy relationship can be taken to the next level with some relational therapy every now and then.  

That is great that he shared this information with you, that you were tested (and hopefully everything was okay), and that he continues to answer your questions about the event.  It sounds like you are still having some trouble with what happened, and that is okay, and normal/natural.  The question I want you to focus on is why you want to know if he had sex with a prostitute?  I want you to think about what this information would do for you, how you would use it, what-if anything would change in your relationship because of this information.  I also want to ask yourself if you feel like you trust your husband?  Has he done anything like this in the past or since he shared this information with you?  

I don't have an answer for you and you may never know, because it sounds like he might not even know.  He did share this information with you, he did make sure to care for you and make sure you were tested for stds, and he does continue to try to answer your questions.  I'm sure he feels a lot of shame and guilt about this experience and understand that you are still feeling hurt and confused by his actions.  

I think it is important to explore the event, how you are both feeling about it, and even discuss ways to feel safe when he travels again if that is something that is causing stress and anxiety.

Unfortunately, you will never know the true answer. This is really frustrating to hear, but you will never 100% be able to guarantee that he has given you the truth. So if you can, work on accepting that, breathing through that,He may not fully remember, he may have lied to you in the past or he is lying now. He may have been honest then or he may be honest not. 

As for options, you can talk to him and provide a safe space for him to tell you what happened. This could be a private conversation with you or at a counseling session. He would need to feel safe to tell you the truth. But remember, there are no guarantees. You would need to make a decision to trust him or not. And go from there. A couples counselor can help guide that conversation, and make sure that he is feeling safe to share. 

More important than if he actually had sex or not, I would evaluate your relationship. Do you trust him now? Were there trust issues before? Does he hide things now? Identifying your current trust levels will be important for having a healthy relationship now. Hope this helps, even if it is frustrating to not have guarantees.

It sounds like you've been living with this uncertainty for those couple years since this happened.  

The reality is you won't ever "know" - mostly because of the various versions your husband has provided you.  

Infidelity, though painful, does not have to kill a marriage.  Secrecy and dishonesty certainly will though.   I encourage you and your husband to seek therapy together with someone who specializes in couples work.  The longer you wait to do so, the more damage is done to whatever connection you have and the greater the distrust will become. Please get qualified help, for your and your husband's sake. 

The only two people who know the answer to your question are your husband and the prostitute.

The question you did and can answer is the reason you would doubt your husband, which is bc of his multiple stories.

Ideally your husband cares to restore your sense of confidence in the stories he tells you.

If you state your doubts and your interest for the truth, ideally he will produce enough evidence of the truth so you will have facts and can make sense of them.   Hopefully the two of you will do this sense making together, especially if he did have sex w the prostititute.

If he's unwilling to care about restoring your trust in him, then this is a different problem entirely.