Please understand that this is not normal. I am decades older than you and have NEVER been called a whore by any bf / DH, nor any other derogatory term.
You are young, with most of your life in front of you. Please don't waste a moment longer on someone who so clearly doesn't respect you (I would even say despises you). (and if you doubt that, ask yourself would you ever call someone a whore? Someone you loved?)
You say you know he loves you - how does he show you his love? And how do you square that with the fact he thinks you're a whore? I'd like to bet this isn't the only way he abuses you.
This is the person who is meant to love you most in the world. I don't care how much pressure he's under. We all have stresses and pressures in our lives - we don't call people we love names. In fact I have more respect for complete strangers than your DH is showing you.
You deserve better. Your DC deserves better. No child should grow up in a home where their father abuses their mother. Be aware that children often copy their parents' behaviour and life choices. Would you be happy if she ended up being called a whore by her DH? What would you advise her to do if it happened?
You are young. You can have a happy life with someone who respect you, loves you, supports you, complements you. Such people are out there. Your DH is in a minority (thankfully) who feel threatened by women so feel the need to diminish them to 'put them them in their place'.
Please get out and make a better life for you and your DC. You will get all the support you need on here.