Q: Why don’t Christians celebrate Hanukkah?
A: There is no good reason.
Christians believe exactly the same as Jews up to the point in time known as Christmas, the birth of Christ and God manifesting herself as a human; however, zealous and/or ignorant Christians have tried to separate themselves from their tradition. The reasons for this usually have to do with hate, money and power. Why else would one want to appear as a hypocrite?
A similar theory is put forth as to why Lilith and Mary Magdalene were re-written by the Christians as it relates to discriminating against women.