I really don’t know how many times I have to say this, at the end of Force Awakens, Luke was NOT, I repeat, he was NOT looking distraught over a lightsaber, he was staring at Rey in disbelief that she was actually right there before him. As such a solid believer in the ways of the jedi, he wouldn’t care about a saber. To him, the saber is just a tool.
If he really cared that much about the weapon he wouldn’t have thrown his away so carelessly in Episode VI. As a believer in Rey Skywalker, Luke was shocked to see his own daughter standing in front of him. Please never say that he was upset over a light saber. The man was visually crying, crying over REY. Let this end the subject forever.