Pathalogical Liars

I am still having a hard time after 16 months of separation from the narc getting him out of my head. There is not a day that goes by where I am not reliving the past and going over the stories and all the things he did and trying to understand how I didn't see any of the lies. Now they come back to me and I see how all the lies, stories don't ad up. Why did I not see them back then. My narc was the nicest, sweetest, non jealous, non controlling person I ever had in my life. He had me so convinced that we were best friends and would spend our lives together up until literally three weeks before we separated. BANG!!!! Out of know where I find out he's cheating on me. "SHOCKED EVERYONE!!! I was so devastated as there were only maybe 3 bad behaviors he showed me during 13 years with him. We rarely even argued and when we did, he was never cruel and it ended in minutes. What he did do to me was lie about his sex drive. Cut off all sex and intimacy about 4 years after we were together and his excuse was that he had no drive, was embarrassed, would take care of it or see a doctor if he couldn't work it out on his own, said it was from his high blood pressure meds. Boy he had me and everyone convinced! I loved him, he was my best friend and I excepted that. Imagine how shocked I was to find out he was having an affair???? All this happened while waiting on test for a brain tumor, blood disorder so very sick, my mom in the hospital, my sister just diagnosed with breast cancer and so much more. Sad, but now looking back, I feel so used as once I got him in as a partner in the company he works for, paid off his debt for schooling his daughter, getting him back on his feet and now life was finally good for us financially, he kicked me to the curb! Don't know if I will ever get over this. It's better as I have really tried to work the program, but I am still letting him in my head daily. I am seeing flags now that he kept so well hidden form me, my family, friends, and co workers. I only survived this because I contacted his ex wives and we have been close friends since and they made me see the real narc! Funny though, he was a different person with all of us. Treated me the best but I'm sure it's because his boss at the time was one of my best friends so he couldn't slip up. I have been in the industry for 30 years and have a great respect from our customers so he had to be careful what he said and did. "Oh, he married a woman 5 months later with three small kids 7,9,12 from Peru, speaks poor English and has no family here. Perfect for him! Do they all lie on a daily basis even when they don't have to?? Are narcs all pathological liars? PS, found out he was a pervert with one wife, charged with molesting a 12 year old, and a cocaine addict prior to when we met, his mom called him a liar on regular bases, brother told ne all the time that his brother had serious issues but never elaborated on it, one daughter hates him and refuses to see him, his son text me after the break up and said he was sorry that I was another one of his dads victims??? New wife text me pictures of her and him, calling me all sorts of horrible names on his company phone until I put an end to it. Tells me what kind of person she is. Sorry, just needed to vent. Seriously, would have been easier if he was cruel up front but I never seen it coming. Are they all so good at lying?