Then I think you got the Good Ending of the Real Route, i.e one of the main endings. "Real" in the name of the route refers to the Real Robot genre of manga/anime. True Ending is a completely different thing, one of the hidden endings, and is just called True Ending. Unless near the end of the game you downloaded some mysterious file attached to a message and then used it on your mecha, because that's what unlocks the True Ending (technically you also need to make previous choices according to other messages, but there's about 6% chance to just blindly guess these). And yeah, the True Ending seems to be the happiest one you can get in the game (still a bit bittersweet, but I guess what else I can expect from a game inspired by mecha anime?). In another comment I posted a not-exactly-guide containing hints how to get each ending, will add the names of routes and endings for more clarity. If these hints aren't enough, just ask and I'll help.
Oh, don't worry, I'll figure it out - I was saying a guide would be nice overall, but I don't usually use guides unless I'm REALLY stuck. But since I'm a bit busy at the moment so I won't try all of the endings, and liked the ending I got anyway, I wanted to know if there is a happier one for my to try and get. And yes, the one I got is the good one from the Real Route then. As for the other one, I see what you're referring to, but I got only the bad version of that one since I was aiming the main route and used that save file for that choice by the end. I'll replay once aiming for the True Ending then! Thank you!