@Losingmymind,
you are concerned, and rightfully so. He cheated on you once. Now he has a private number, and like the other cementer said, these services he joined with are farrr beyond looking at porn. He should be open 100% scared to death to loose you if he cheated once and means what he says about it being the last time. Not exactly a trust building thing going on here. You should take this all very seriously in light of your past with him involving other women ..