Can I sue my husband’s ex-lover for slander?

My husband and I were separated when he met another woman. She became pregnant the same night they let. They were together while we were separated and she had the baby. We have now reconciled, but she continues to harass him in regards to the baby (which she left his name as the father off the birth certificate, so there is no named father) but also text him and say terrible things about me and our children together. She has also tried several times to get both me and my husband fired from our jobs. She also tries to get my husband to go back to her and sends nude pictures to him. Is there any point in suing her? My husband has told her to stop repeatedly and he feels he has to communicate somewhat because he is the alleged father of her baby. Do I have any recourse? Mostly concerned about what to do over our children and my job, but it is also causing me a great deal of stress and health problems.