2lostandconfused, I found it extremely distracting that you used "they" instead of "him" or "her" in your post. This is an enormous world wide web, it's unlikely that anyone will know who you are talking about if you name the gender. I wouldn't pick nits about this, except when you said "they" I never knew whether you were talking about your spouse and the colleague, or just your spouse, or just the colleague.
I also think you need to stop apologizing for noticing that your spouse is cheating on you. If you have to pay the phone bill, don't apologize for noticing what's on the bill you are paying. Don't appear to be in the dark about why your partner is going to a hotel when he/she is "sick".
You deserve to know what is going on in your relationship. Enough of your partner acting like you don't have a right to know, and to act on your own behalf.
First of all, most marriages i think have an open full disclosure full transparency of their accounts, so don't be hung up feeling guilty about finding out what's been happening. If it hasn't been your right to full transparency , it should be. You might as well try to be as calm as possible. and that will help set the tone for ah honest conversation. Accept the truth, with dignity and composure. Take it as a by product of having a place to discuss your situation, and benefit from not being alone in all of this. The reality is you need to know the truth above all else, and he'll be more likely to tell you if you are not showing him that are going to fall apart. The fact is that now is not the time to fall apart, now's the time to save yourself from being the unwitting recipient of more lies that would waste your time. Bottom line, you need the truth and you need to think about how you would deal with him having an affair. Before you do anything, you have to talk about it with friends, You can do that here. You're NOT ALONE. You have many here that will walk through this with you. I'm sorry you're going through this. May God be with you and keep you strong.
"I hope you can come home and be you."
I'm concerned that you would be willing to accept that he might be having a relationship and all you're saying about it, is that you want him to act like it didn't happen.
ps -- And, if your relationship is in trouble in your spouse's mind, frankly it is in trouble, period. You can't unilaterally change things if your spouse is on the way out the door emotionally.
It sounds like your spouse is having serious regrets, even if he or she is not cheating. Ask if he or she wants out. You may as well know.
I'm not surprised at someone being angry when you said "I hope you can come home and be you." Sounded like "Now that in the middle of your existential crisis I have been a good sport about you having two days away, I hope you have gotten this nonsense out of your system and are coming back to be mine as you should." In the middle of a crisis, someone would hear your comment that way even if you just said it out of worry and concern.
Ask what is going on in your relationship (not what is going on with the old colleague). Be ready to find out that in your spouse's mind, your relationship is in trouble.
You are using the words "they", "their" and "them." Are you referring to him?
I hate to say it, but it sounds like he's slowly detaching himself from the marriage. Sounds like he never had closure with this other person.
You can approach him about this by asking him what's going on and if he happy in the marriage. I wouldn't bring this up as soon as he gets in the door. Wait for a time when you feel more calm and he is calm. Don't approach him in an accusatory or angry manner.
Tell your spouse that no matter what, the truth is the most important thing. Assure them that you won't flip out and be angry with them if they tell you the truth because as much as it might be terrible to hear, it's better hearing it now as opposed to later down the road. Think about if your spouse seems like the kind of person that is willing to lie to you. Have they lied about anything else in the past? Are there any other incidents that would make you believe they are lying? Or is this a special circumstance? I myself have lied to my partner about pretty important information before, not exactly being unfaithful, but I can partially understand people's choice to lie. Not that it makes it okay, but I can empathize a little. I'm not the greatest with giving advice, but that is what I would do personally.