Thank you for your advice. He never makes comments about his relationship unless I ask. He mentioned last week that they haven't slept together since March. His reasoning was that she has no sex drive, but that he doesn't feel any sort of emotion when they do sleep together because all he thinks about is me. From what I can gather, I'm very like him sexually and very open minded, she doesn't seem to be interested at all in that. But then I can't say he uses me for sex because we don't see each other often so I don't feel like im even filling that void. I've never even asked the question of whether he would leave her for me. I really don't want to be a homewrecker either. I feel terrible enough with being the other woman, I just haven't been able to cut him off as yet because I genuinely believe every thing he says to me, he makes so much effort with everything, he is always there when I need him, he worries about me as at times my mental health hasn't been great, he was there when my grandparents passed away and when I lost my best friend so I don't think I'm being naive that he's only involved with me for his own gain. Because he has done so much for me. Obviously, he's a cheat, he's disrespecting his partner and they are bad points but he's never given me any reason to think badly of him in any other way. It's just so hard. I really do appreciate everyone's advice, its nice to get more perspective on it as nobody knows about us at all.