Separated from spouse can I file head of household?

Around the end of April last year, my husband and I decided to separate. It wasn't a legal separation as it was like a trial one since neither of us really believe in divorce. He moved into a home he owned where his dad lives. We didn't change anything like the names on the utilities, he still received mail at our PO Box and we still had a joint back account, as well as our personal ones. After some time, we have decided to get back together as of earlier this month. I thought I would have to file separately but it looks like it would be better for me to file head of household. We do have a 3 year old who lived with me during the time and I paid for more than half of the house expenses. Can I file HOH?