The characters on the screen should CARE for what is happening - and their emotions needs to be as strong as possible (because of how 'mirroring' in reader's brain work).
If the character 'doesn't care' - then the reader 'won't care' either.
I think you're making a mistake here by presuming that "doesn't stalk = doesn't care" and that this pathetic behavior is the only way to show that the MC is emotional about the subject.
We have direct insight into MC's thoughts, so the game can simply show to the reader that these thoughts exist, that MC is potentially worried about Emily and Tyson getting close. That it bothers him --and also, that's a good opportunity for some introspection
why it bothers him-- etc and so on.
But ffs, it doesn't mean MC has to
act on these thoughts like a cringy creep, especially without taking any input from the player. The things which people point out regarding his own situation, his thought process should acknowledge these too. That way you have
even more, conflicting emotions going on in his head, which you say yourself is what should be happening to keep the reader invested. Then leave it to the player to decide if they want to stalk his friend or if they'd rather not. If it's your decision and not just railroaded MC's action that'd alleviate the frustration the sequence currently creates for some players.