Lizzie You really need to confront this man because if you don't it only paves the way to unhappiness and heartache (for you). Six months in you should be exclusive, unless it's just a FWB type relationship, so in no way is it too soon to discuss this with him. At least if you confront him, you'll know once and for all what the eff he's playing at, and can make a decision either way. You could just start off by saying 'The other night when you looked at your phone I saw xxx website on your browser. I thought I must have been mistake but I looked at the site and have seen your profile and noticed that you've been online recently. I think after six months and some great times together, I'd like to know why you're online and what you're planning to get out of it.' Do it face to face, not to see him squirm as such, but you'll be able to read his body language and tone of voice much better in person. You never know, he may apologise profusely and say he'll remove the profile. Be prepared for this to be the end though. Let's face it, do you really want to be with someone who thinks it's acceptable to be online dating six months into a relationship with you?
Scarey Right, I've read the Matt Hussey book (if you google, there's a free pdf download available, btw) and he would say two things to you. Firstly, don't make yourself too available. By that I mean, don't always keep those weekends free that he doesn't have his daughters. Plan stuff to do with your friends and family and if he mentions going out, tell him you already have plans but might be free on x date (a different date). Do not ever drop your pre-made plans for him, no matter how much you want to see him. The other thing he'd probably say is, only put in what you're getting out. You say he's met your DDs but you haven't met his. Don't arrange any more outings with your kids until he introduces you to his. You need to match each other in terms of the effort that's being made. Don't dance to his tune - dance to your own.
Bumble Someone (Lizzie, I think?) recommended Matthew Hussey on a previous thread. I downloaded a free pdf of his book and read it quite quickly. It's really excellent. The download version has video links where you can watch clips of him during his seminars - he is gorgeous. And his advice is spot on, which helps. He runs seminars in London and I'm hoping to attend one in the next few months.