BF troubles

I've been with my BF for little over a year. We have fights but lately they are almost every day. The latest fight was about me messaging an old guy friend of mine. (He's like a brother) my bf got super jealous and started a fight saying I was lying and I didn't even lie. He went through my phone and was mad because I didn't tell him about it. Do you think it was necessary for me to tell him stuff like that? I really didn't feel that it was a bad thing not to tell.