I don't think he's telling me this stuff to make me jealous, it's just what I've picked out of general conversations we've had - he's been friends with the bloke since primary school. The girlfriend has been around for 7 years. He's pretty lax with his phone, he never hides anything on it/takes it to the loo etc so I see her messages flash up - nothing untoward at all, it's just the volume - like she's always reminding him she's around and he's too nice to tell her to fuck off. He even told me about an ex girlfriend of 10 years ago getting in touch the other day on FB asking for a friend request, but he declined as he didn't think it was appropriate - he actually has 1 friend on FB - his brother 
I honestly don't think he has any feelings for her, but I can bloody well see she's lining up to make her move on him - do I just let it happen and hope he rebuffs her when it happens?
@vwman - Fuck there's a phrase for it? Shit's getting serious now 
They're separating because the friend is at work all the time (so his gf can be a sahm...?), they argue because he doesn't help with the kids, she'd rather be out partying - she's only 28, feels like she's missed out on life etc. Friend is back on Wednesday.
Mr Cornish - 4 bedroomed farm house, beautiful location, solvent, good prospects, kindest, most considerate man I've ever met, no ties - would be a massive improvement on her current situation.
I know he wants me - he's sent me 3 messages I've not yet replied to saying he wishes I was with him today as the weather is so lovely and how much he enjoyed our weekend together and can't wait until we see each other on Wednesday. I could cry, I hate myself for feeling so insecure.