How do you quickly decide which lies are deal breakers & swiftly take action?

It's been said that early on in dating.. people at times share a few white lies here and there.. But when you find that he's lied about his age, and then his living situation. (I think he lives alone.. to... His ex comes and goes to... She's actually lived with me for the past 8 years)... Learning that he says he is in the UK, but something else says he's in the midwest... Him not knowing what time it is there... (until enough time was given for him to possibly google it).. in addition to many other flags... I still went with this.

If this had happened to a friend of mine.. I'd be freaking out on her.. saying.. are you frick'n CRAZY!? They say.. once a cheater always a cheater.. once a fabricator.. always a fabricator. Why on earth would I want anything to do with a person capable of such deception. So then I conger up a test to see what he's really all about... After sleeping together.. I say.. well.. I'm thinking that maybe I need to take a step backward & cease sexual contact.. I've been going to church and I want to do what is right. His response: I feel bad, but I can't hang with that. Giving me the answer I already knew... unhonorable selfish intentions. It's assholes like these, that are the hardest to recover from. Why could'nt I just of swiftly cut ties after finding the first two lies.. or even.. think it was odd.. he wanted to kiss me and stroke my face within the first 10 minutes of meeting me? Why do I continue to give people the benefit of the doubt? Why do I continue to make excuses for them and only want to see their good qualities? Better yet, why do these f**k faces appeal to me most?