Rachiv,
It is sad to read some of the insensitive replies on this thread.
You should most definitely keep up a good relationship with your family (except in some unusual situations). They are good people, too.
JC is a very very complex topic. There are mainstream opinions. There are lesser known opinions. There is also much that was made up, and much that we don’t know.
When with your family you should seek common ground. For better or worse, early Jewish xtianity promoted the Torah commandments for Jews and the 7 commandments for non-Jews. When the non-Jews took over, they seriously confused many things. But in any case, there is still a lot of common ground. The fact that xtians do not follow most commandments is still in agreement with the Jewish position that they are not commanded to.
So focus on what we agree on. There is so much. Most of the rest you can say we really don’t know all the facts. Some things you will have to respectfully differ, but with the attitude that this is right for me.