If MC didn't choose any of the proposed ones he automatically romances glade despite the fact that he completely avoided any contact with her.
This is partially true. I addressed this a while back, but romance and family are key pillars of Tides. I appreciate there are a small minority out there who don't want to romance any of the LIs and just want to experience the story without the romance. However, I've designed them to go hand-in-hand, and the story just wouldn't be the same without the romance. Thus, there is no "monk" path in Tides where you can reject all the LIs.
Now, the reason why you're forced to romance Glade is because she's the last one you can decline. I notice there is some confusion with regards to rejecting her, and then being forced to romance her anyway, and perhaps I should try and make this more clear in game. When you say no to Glade just after you capture her, you aren't rejecting her as a Love Interest, but as an ally. You can still romance Glade regardless of whether or not you reject her offer.
Hopefully this clears it up a bit. I'm afraid that if you don't like any of the LIs, then Tides probably isn't the game for you which is perfectly fine because everyone has different tastes
