We've been dealing with this henious crime for several years now, and it's showing no signs of retreat. High-waisted bottoms have been slowly creeping into style this year, but not enough people are taking the bait. The muffin top is still a raging plague, folks, and we need to stop it.
Let's take another look at the picture. That girl is NOT HEAVY, and yet, those shorts are squeezing her like a marshmallow in a vice. She's obviously not so large that she can't find clothes to fit, so what are we left to assume? Girlfriend is wearing the wrong size.
There is no shame in going up (or down) a size to get the appropriate fit. I will freely admit, ladies and gentlemen, that I have to switch sizes all the time. Just a few weeks ago, I tried on a pair of jeans that gave me Sausage Leg Syndrome (a dibilitating condition similar to the muffin top), so I went up not one, but two sizes, and they were still wonky. So you know what I did? I walked away. Those were obviously not the bottoms for me.
Unfortunately, the young lady in the picture did NOT walk away from those shorts, and is GUILTY of a fashion crime (so is her beau, actually, but that's an entirely different can of worms). Don't let the same thing happen to you. Everyone deserves well-fitting clothes.