Cutting? How can i talk to him alone? what should i say?

Get him out of his comfort zone, the text realm. It is a million times easier to lie over a text then it is in person. Look into his eyes and you may know when he's lying. Point it out when you think he is. I think you are in a relationship with either a compulsive or pathological liar. You need to make it clear to him he needs to change. Hope this helps.