Her friends are happy, they have family, a husband, kids! She wants that too, but she can't. She chose her farm over love, now it's coming back to haunt her.

Ships (just so you are prepared)
RD x Soarin - kid: Thunder Dash
Rarity x Fancy pants - kid: Ruby and Sapphire
Twilight x Flash (I am so sorry) - kid: Jupiter and Comet Star
Fluttershy x big Mac - kid: Applesky, Flutter Leaf and Flutter Apple
Pinkie Pie x Cheese Sandwich - kid: Lollipop, Jelly, Bubblegum and Minty
Spike x Sweetie Belle - too young for kids!