Applejack has always had a thing for Twilight, but never had the nerve to admit to it under the circumstance of Twilight's royal status. Applejack knows that she is a friend that Twilight trusts, but how can she ever love a lowly farm pony such as herself? But sometimes penting up feelings can become too much, and you just have to spill it out. So she does it through what she does best; and that is farmwork.