Hacker trying to get into my email and using my ip address

There is a hacker trying to access my hotmail account several times a day. I always check my recently activities and from there I could see someone else inserting the wrong password about 20 times a day. This person is also using my ip address. Only my husband and I live in the house, he knows my email password, so for sure is someone else other then him doing this. What Can I do? How do I run norton on my email account? We have a mac. Thank you.