im too scared to do the last two options for the ending..
what happens in the 2 other ones that isnt confronting the stalker..? :(
Non spoilers: They are sort of like a scale. Confronting is the best, happy ending, running away is still generally a happy ending, although it doesn't reach the same conclusion as the first, and the third... I just obtained it now, I do not want to go through it again.
Spoilers:
Second ending they simply run away to a friend's place. They stay there for some time, and things seemingly get somewhat back to normal. They decide to not exactly put a label on their relationship, but keeping it unique. They are still close, happy, and have a fun time that night.
Third ending is you do nothing. You suggest staying with Robin, but he tells you to go to sleep. You do, and eventually, the stalker barges in, locks himself with Robin, and attempts to come at him. You break down the door, and beat the stalker mercilessly. Police eventually arrive and take him away.
But, you betrayed Robin's trust. You told him it will all be ok. And it wasn't. You slept soundly as he was trembling in fear. He decides to leave, not feeling safe around you anymore, feeling as if you don't care. This is by far the worst of the endings, and I genuinely feel awful doing it, even if it was just to 100% complete the game (I decided to replay the first ending after to let them have a happy conclusion).