Before "Where The Apple Lies" I always thought they would end Spike crush on Rarity by having one of the cmc take notice of colts and get a crush on Spike. Then Twilight, Rarity, and if it wasn't Sweetie Belle the other big sister would then try and get to get over Rarity. But then "Where The Apple Lies" came along and show us that there bigger age gape between Spike and the cmc then Spike and the mane 6, so now it time for this crush thing to end or at least change. The only way I see this happening now is for a mare to get crush on Spike and depending on how old the mare we it could go one of two ways. If the mare the same age as the mane then we that would mean that Spike is five years younger then Twilight(like what everybody thing he is anyway) and could stand a chance with Rarity. In this case we could see Rarity start to feel the same way as Spike, but I feel this unlikely. The second way the mare would be a teenager and then we could have Spike realize that he to young for Rarity and start to try and move on from her, and failed mostly. I find this one the most likely of the two.