Obito loved Rin, Rin gave Obito plenty of attention and basically teased him, she liked Kakashi but Kakashi was dealing with the suicide of his father and didn't care for girls. Obito had no family and team Minato became his family like Naruto he was obsessed with keeping his promises like the ones he made to Rin. When Rin was killed his world was shattered because in his mind he no longer had a family he had nothing. Uchiha's seem to all have severe OCD, which leads them to become problems as Tobirama explained, but thus was Obito's downfall.
What's weird is that when he does die Rin greets him and seems like she's been waiting for him all this time, as if she was impressed he lived his life for her and now likes him. He states if Kakashi joins them it would be ruined, is he threatened by Kakashi because he knows Rin may be drawn to him instead? He want to be alone with Rin, so his fantasies can be realized, but this kind of makes Rin seem promiscuous. Obito's gettin it and he knows Kakashi would be gettin it instead of he came up there, kinda interesting and makes the whole relationship of Team Minato seem more complicated. Obito knew Rin liked him, but she saw his as a loser compared to Kakashi, he wanted to impress her so bad so she'd accept him the way he wanted, when he died and made it to heaven their feelings for each other were a lot more honest.
What's weird is that when he does die Rin greets him and seems like she's been waiting for him all this time, as if she was impressed he lived his life for her and now likes him. He states if Kakashi joins them it would be ruined, is he threatened by Kakashi because he knows Rin may be drawn to him instead? He want to be alone with Rin, so his fantasies can be realized, but this kind of makes Rin seem promiscuous. Obito's gettin it and he knows Kakashi would be gettin it instead of he came up there, kinda interesting and makes the whole relationship of Team Minato seem more complicated. Obito knew Rin liked him, but she saw his as a loser compared to Kakashi, he wanted to impress her so bad so she'd accept him the way he wanted, when he died and made it to heaven their feelings for each other were a lot more honest.
