Panel 1: We see Liz sitting on her bed wallowing in self-pity because she assumes that getting eyeglasses means that she's just going to be this ugly thing no boy will ever like. As she does so, we notice that there's a teddy bear with a smile sewn onto its face. This becomes important.
Panel 2: This is because she notices it out of the corner of her eyes.
Panel 3: She stares at it angrily.
Panel 4: She then yells "STOP LAUGHING AT ME!!!" because she's kind of the same sort of loon Elly is.
Summary: This, I think, is why any attempt people might make to make her happy are doomed to failure. Simply put, she assumes that if people aren't laughing and calling her ugly and stooooopid, either they're lying or something is wrong with them.