He may have always been a jerk but you never really allowed yourself to see it.
You may have been so caught up in his looks or in how he made you feel that you never allowed yourself to see the signs.
You never allowed yourself to acknowledge that moment that he was rude to his friend or that he swore at a driver who casually entered his lane while signalling.
You never allowed yourself to acknowledge when he made fun of someone he didn’t know and got a nice laugh out of it.
You probably even laughed along.
You never allowed yourself to acknowledge when he insulted you but quickly covered it up by giving you a compliment.
You never allowed yourself to acknowledge when he showed up late for a date and he didn’t really give you a genuine apology.
You never allowed yourself to acknowledge when he cancelled on a date and didn’t bother to let you know until you were forced to text him to find out what happened.
You let it pass.
As human beings, we can become incredibly emotionally blinded when we really like someone.
You were most likely giving excuses for him and you didn’t even realize that you were.
You just kept allowing yourself to get so caught up in how attractive he was or how he made you feel that you refused to look at the numerous clues that he would leave in his wake.
He is being a jerk now because he has most likely always been one.
You just wouldn’t allow yourself to take heed of all the signs that he was showing you along the way.
He knows that he now has your heart.
Thereby, he knows that he can get away with even more bad and jerk-like behavior without having to worry about the penalties.
You are all in now and it is going to be a lot harder for you to let him go than if you had just recently met him and barely knew anything about him.
This is how it goes in these scenarios.
On the flip side, you may have even noticed some of his jerk-like behavior earlier on but you made yourself believe that this is just how he is and that he would get better.
You just allowed yourself to focus on how amazing he made you feel or how much he made you just want to be with him so bad.
You allowed your incredible desire to be accepted by him to completely take over.
There may have even been elements of his jerk-like behavior that appealed to you initially.
You saw them as a sign of strength and that he wasn’t a guy who would take things lying down without retaliating.
Now, you realize that nothing about his jerk-like behavior was a show of strength.
If anything, you are now looking at this behavior as an impediment to his personal growth.
Well, he knows that he can get away with being a jerk because you have always cast a blind eye to it.
As long as that remains the case, he will continue being a jerk.