You will have to, Your father Grandmaster of the hatred Order, your whatever Kaija is for you, elite Operative of said institution, your mother retired elite operative of said institution and suports your father.
If you burn bridges, and join the counterpart, you will have to face them sooner or later.
besides the conflict of the Alfar and Templars is not the main dish, the danger of a take over by corrupted and dark forces is.
which will erase all resistace, be it the Alfar (they want their resorces) or the Templars.