If you are in an abusive marriage the RIGHT thing to do is get out. Get in contact with your local women's shelter so they can help you plan. You should not stay in a situation where you or your child are in danger.
It would not be the RIGHT thing to immediately get involved with someone else right away. Before you move on with another relationship, you have to get yourself emotionally healthy and make sure you have stability for your child. You need to work on YOU. This other person is making you feel good, feel loved and this is not good for you in your state emotionally. Is this other person married as well?
When things get tough like they have for you... you are seeing the grass as greener on the other side. it is not always bells and whistles. Truthfully, you are not in love with this other person, you are in love with the idea. You are in love with the idea that this other person is going to rescue you.
Does your husband know about this other person? If so, you are not only endangering yourself and your toddler but you have pulled a third party into the scene. If your husband is violent and abusive, he could very well go off the deep end and harm you, your child or this other person.
You do not need to be looking for love right now. You need to be talking with a counselor to help you through your current marriage and determine what you plan to do to get yourself healthy again so you can be a stable parent for your child.
Get your priorities straight.... YOU and YOUR child should be your priority.
Best wishes.
ETA: Nice catch Jennifer. I can't believe I fell for it.