Who does Mikasa fall in love with?
Yes! Mikasa actually loves Eren in a romantic way. It is heavy hinted and implied throughout the series that Milasa loves Eren.
Does Armin and Mikasa end up together?
Eren, Mikasa and Armin have separated right now. Mikasa and Armin are still friends, but there is clearly tension between the two of them caused by Eren’s decision to use a full scale rumbling (meaning he released all the colossal titans inside the walls) in order to wipe out humanity beyond their island.