Its a hard decision a very very hard decision.

because "what if" weighed on her mind.

But she hasn't been going out with the guy, and she hasn't been avoiding SOBO. So it doesn't mean anything.

The problem is that everyone seems to be assuming that she is going to leave when she hasn't been doing anything with the other guy nor has she been cutting SOBO off for the other guy either. Also, the guy that has his girlfriends mind racked at the moment doesn't even live where SOBO and his girlfriend is and is going away so when he leaves she is still going to be with SOBO, you didn't read that? The main thing SOBO is asking is that he wants to know that her mind is going to be on him and not the guy who came for a visit.