If you believe Jesus is the messiah, you are a Christian. Why don't you just say that proudly? Just as people can convert out of Judaism, they can convert into it. It's not a racial thing, so what you were born is irrelevant. I know it's probably hard on your family. Maybe this is the root of your reluctance to say out loud that you are a Christian. Celebrating Hanukah and Passover do not make you Jewish. Your beliefs make you Jewish. Jews do not believe Jesus was the savior. You are a Christian. Stand up and be proud about it!
Unfortunately, over time the term "Christian" came to mean more than simply a "follower of the Messiah." Many people today have a false dichotomy in their minds, that on the one hand, there are Jews and Judaism, and on the other hand there are Christians and Christianity, and supposedly you must choose between the two.
Accordingly, when a Jew accepts Yeshua he is thought to have "switched over" from the Jew-Judaism side to the Christian-Christianity side, and is therefore no longer regarded as a Jew, but a Christian.
For all intents and purposes the term "Christian" has become synonymous with "non-Jew" or "Gentile." We believe the opposite to be true. Nothing could be more Jewish than to follow Israel's Messiah! Consequently we choose to call ourselves "Messianic Jews" which identifies us as Jewish people who follow Messiah Yeshua.