He rises from the bed, and says to himself sadly, " Damn, I was meant to protect her! Later, Packie will phone, in tears, and says that Kate should not been killed and that it was the male Mc Rearys who were sinners.
And he is looking after his mother as he is all she has left.
It is possible that one of the PMP 600's is Brucie's, due to his liking of sports cars, but it's unlikely that the other PMP 600 is Bernie's, as Bernie mentions that he doesn't drive and only walks or takes cabs.
It's likely that the vehicles were rented for the wedding to taxi the guests.
After completing the mission and saving the game, the save title will be "In Mourning" instead of "Mr and Mrs Bellic".