How often and what makes sag lie to their partner?

How often and what makes sag lie to their partner?

My ex Sag man lied a lot. He lied about the big things like being married but seeing how he was actually cheating on his wife with me, it's understandable for him to lie to get what he wants. But, he would lie about the small things that I just won't understand why. He showed me a picture of his colleagues and said he took it that morning while it was actually 2 months ago, lied to me about opening up a restaurant that was actually an online catering service which lasted for 4 months before failing, lied to me about going overseas for work for 2-3 days which didn't happen and many others.