It's a reflection of his ability to cover his tracks, silence witnesses, and of his trusted briefs' knowledge of legal loopholes that Phil's only been in prison a few times.
Originally a nicer guy, he was conned by so many people he eventually took on a crime boss mantle as a way to get revenge on the world.
Sharon would usually turn to him when she and Grant had a row or Grant gained physical violence.
They sleep together, but she chooses to stay with Grant.
He gave her the money and she was never seen again.