JP is seriously annoying me too. I don't recognize him right now, the way they have been writing him since he blabbed to Nathan is awful.
He knows what James is like, he knows how damaged he is because he has seen it and because he has been told.. "I don't even know if I'm ever going to feel anything again". He knows that James has always avoided intimacy and emotional involvement, and he knows why... if he chooses to pursue a relationship with him he should do it responsibly, knowing that it won't be easy, and with the will to help him and stand by him when he inevitably messes up or regresses.
I'm not seeing any of that, I'm seeing someone who, pushed by circumstances, sort of forced James into a rushed cohabitation he wasn't really ready for, and throws strops when things predictably aren't the way he wants. I'm npt seeing the love and the thoughtfulness a situation like theirs would require.
If JP wants the perfect partner and perfect father figure for Matthew, he shouldn't indeed be wasting his and James' time. He should go be with Scott or someone more adjusted. If he chooses to be with James he has to be aware of the challenges it entails, and be willing to fight for it, not give up at the first hurdle...because there will be many more.