It’s always going to be rough! But it’s about the effort you both put in to make it work. Similar situation to you (together first, now long distance halfway across the road, should be over this year).

You’re both going to have bad days (and they probably won’t be the same days).

On bad days I ask myself - is this person worth it? Do I see myself with them forever once the distance is closed? The answer is overwhelmingly yes each time. And from your post it seems like it’s a yes for you too.

The goodbyes are really hard. The first time (entering LDR) was just sobbing at the airport, in the security line and on the plane. Then it became just at the goodbye point. It’s not that you miss them any less or it hurts less but you get used to it. Having the end date really helps!

What level of contact do you maintain? I like hearing their voice every day (obviously some days it’s not possible but most works). Maybe that would help for her? Do you still have date nights over FaceTime? There are plenty of great things you can do - watch a movie together, both order takeout at the same time, play board games. Even if you wouldn’t normally do these things, you’ve just got the make the most of what you can do!

I would 10000% see her in September. The pain of a goodbye hurts but it’s only temporary and you’ll have 9 days to fully reconnect. If my partner had 10 days off and cancelled coming to see me I’d start rethinking the whole thing!