I'm so sorry you have had to endure that obscene behaviour from another adult. Disgusting.
Please end your friendship with this couple. The stress isn't worth it.
As for your husband. Can you sit and talk to him about how the behaviour makes you feel? How you don't want to be friends with them anymore because of their behaviour?
in all honesty you don't owe the lady anything. Yes she helped you at a time you needed help but she sounds like she's not very nice.
Surround your self and your kids with positive friendly role models. You don't need their toxic friendship