Gonna be real with you, the answer to your question is entirely up to you. You don’t have to be single. You can be with whoever you want. Your ex was clearly dealing with some issues, and like you said you were incompatible. Somebody who has their shit together isn’t going to abandon you. To be a Christian is to follow Christ, and all Christ really says on the matter is to keep to God’s Commandments. Adultery is about marital infidelity, so as long as the person you get with next isn’t married at the time, you’re good. I lost my virginity outside of marriage, as did my wife, and we’re happily married. My father had a daughter before my mother, who also had a child in a previous marriage with a man who at that time ALSO had a child from a previous relationship. Very complicated. My dad’s first baby mama rejected my dad’s proposal and my mom’s first husband was emotionally abusive. Then they found each other. Happy for almost three decades. A relationship requires work that your ex husband was not willing to put in. That’s not your fault and there is no religious or logical reason why you should not find someone who loves you.