About to be a LDR

My SO and I have been together for about 3 years and a half and this fall our relationship with become a LDR for the first time. We haven’t really talked about what’s going to happen when I move and it scares me that he’s just not into it. Every time I try to bring it up he tells me not to worry but that he doesn’t want to talk about it or he’ll just cut the conversation short. It’s sad to know we won’t be together as much but I know we can survive it, but lately we’ve been fighting about stupid things.

What tips do you recommend to keep the relationship healthy while being away from each other?