@Sadmom,
Should you go? No one here can answer that but you. IMHO, that’s nuking the marriage without any indication of cheating or even talking to another. Pretty extreme reaction.
I hear your sad and understand your upset. However, I see not one word that he has cheated on you with another nor have you written that there was a sign of his disloyalties. I do see he lied about his actions. That would ups t me if I were in that situation.
You write that you feel insecure but has even contacted a real person? I’m only guessing that perhaps he has not.
After three childbirths you may have certain feelings/insecurity about Your physical appearance. You AND your hubby have to work together to restore your confidence and work to help you feel loved and appreciated.
Perhaps, try watching porn together might work? I’m no expert by any means. However, if that doesn’t work and he continues then you need to not feel inadequate if he does watch porn.
He also has to stop hiding it and be honest. This is not your previous relationship even if it feels like it might be heading that way.