The gray area of flirting with someone else.

I haven't checked in on here in a while...It's been hectic with work, out-of-town visitors, and now me being super sick.  I'm going on a week tomorrow of an upper respiratory infection that totally has me knocked on my ass.

I came across something today though that I had to get off my chest, and I really didn't know who to turn to, besides you girls. 

Last night as I was heading to bed,  Mike was out on the couch watching tv.  He had had a few drinks and was curled up with a comforter and pillow looking quite comfy and I said, "Oh, are you going to sleep out here tonight?"  He said he might, because he was so cozy and because I've been so sick.  No big deal.

As I was filling up my water cup and just putting away a few things in the kitchen though, I kept hearing his phone "bing" and realized that he was texting like crazy...very unlike him, as he really hates typing on his phone and hardly will be seen texting.  Last time that he was texting late and had decided to sleep in the living room after a few drinks was when I found out he had been texting X's little sister.  (Remember that?)  So my interest was right away piqued.  "Wow you're blowing up over there!" I said.  "Yah, it's a friend from college.  I don't want to talk on the phone though so I'm trying to wind up the conversation." 

I know him all too well.  A) He thinks I am nosy whenever I make off-hand comments like that, so he normally wouldn't fill me in on who it was.  That he jumped to informing me who he was texting was strange of him.  B) The second sentence explaining why he was texting so much was even more information that he normally wouldn't share.

So today when he got home and went for a run, I did a "bad" thing and checked his phone.  It was a girl, we'll call her AE, who I'd never heard of before.  They had texted for an hour and a half back and forth.  I scrolled quickly through the messages, still thinking they might just be nothing, when I saw in the middle of all the scrolling the words, "I can't.  I live with her."

Obviously, I started from the beginning then and read through each message.  She was reaching out to say hi, how are you.  He said hey, how are you back.  She said nothing, that she was in bed, and that she was going to go visit...blahblahblah.  His response: "In bed huh? ;)"

My heart started pounding.  

She answered "I could have a really great answer to that one, but I'm sure your gf wouldn't appreciate it."  

Him: "You're horny."  

Her: "Someone else is too apparently!"  

Him: "Who's that?" 

And then that thought was dropped.  A bit more bantering and then,
Him: "Would we still be friends if we had had sex?"
Her: "What?"
Him: "If we had had sex, do you think that we would still be friends?"

And then,

Him: "I'm scared of where I'm at right now.  In my relationship and all."
Her: "Can you call me?  I'm worried about you.  I will always care about you no matter what or how long it's been since we've seen each other.  You're the type of person that I would answer the phone to at 3 am to help pick you up from your lowest point.  I will always be here for you.  Call me, I will talk with you about why you are scared."
Him: "I can't.  I live with her."

And then it trickled off and they went to bed.  She texted him today too, but he didn't answer her.

The thing that's so weird about this is that I can't figure out if he did something wrong or not.  I mean, I think he did, but I'm not entirely sure.  Let's just say if it were me that had said those things to a guy that I had almost dated (I deciphered that from the entire text conversation that they had almost dated a few years ago), I would feel super guilty and like I had done something wrong.  He's normally the king of having a conscience and telling me the truth about everything, so I'm really surprised that he actually hasn't somehow told me about it and downplayed it.  And I can't bring it up to him, because then he'd know I'd looked through his phone.

What do you girls think?
***Update:  I "borrowed" his phone to text my sister tonight, and the phone "accidentally freaked out" (my story at least) and landed on the texts that said "What if we'd had sex?"  I brought it to him, shaking with adrenaline, and asked him about it.  He said, "She's an old friend from college who has always had a crush on me, and we were discussing the ability to be friends with ex's or not, because she is having trouble with her ex-boyfriend right now.  And I brought up, 'Well what if we'd had sex?' meaning, would we still be friends?  I thought about it this morning and realized that it was an inappropriate thing to have said, and I'm really sorry."  I cried a little because my feelings were hurt, and although I do think that he was out of line, I do 'buy' his story and said I forgave him, but that he did hurt my feelings.  As for what he was saying about being scared in the relationship he's in, we had a talk about that sort of separately, and he was honest that he doesn't feel as confident in us as he has in the past, and I told him that I honestly felt the same way and can't hold that against him.  We agreed that we want to be together, and we will see where it goes in the long run,  but for now, we are both present here and now.