He is obsessed?

overtime I realized that's why he is obsessed with me is that I remind of his 1st girlfriend that leave him for some reason. But the question is why he is still obsessed with me just because I look like his ex?

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+1 y
He assign stalker to watch/"guard" over me whenever I go, 6/10 I could meet those people the he set for me, and I don't have the deep understanding of his reason for that. When I was in highschool he loved to collect mostly my scarf without my knowing and consent. There's a time that he go to the apartment where I lived without my knowing and I just know it from my neighbor
-room mate.

by the way I'm a college student now, and "guarding" me is still present.
He is obsessed?
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