husband miss his ex

idk what to feel when my husband shared me about his ex and his sex experience. He never say he miss his ex but the way he telling story about them make me numb with a hit of pain. While he talking i try to show that i understand him and showing my interest about it. Just want to let go my feeling here as i am not local and cant tell to my relatives nor friend, idk where or how to let go my heavy feeling. We have 2 kids and when he shared his love story about his ex, my mind running/thinking that am i just substitute or a person that he can afford. To tell u im not materialise, im simple and no branded nor make up. My only spending is for my kid but not myself (plain and simple). He told me his ex like to do girly thing pedi buy bamded and travel thats why they broke up bcos he cant afford. i really dont know but now the feeling is my husband sooner or later he will leave me, dumb me. So i need to prepare myself physically emotionally and financially.