Don't want to be married anymore

My baby is 4 weeks old today and I don't want to be with his dad anymore. 
He disrespects me. He's rude, bossy and unpleasant to be around. 
My dad always taught me to be with someone who makes me feel like a queen- he makes me feel like a slave beneath him. 
He's a good dad so far but I do the lions share and could easily raise my son alone. 
How do I end this?