After Garnet found out about Pearl's betrayal of sorts, she forcefully tells (note she dosen't ask) Amethyst to fuse with her. Sugalite emerged and seemed very... Garnet-powered. Afterward when Steven and Amethyst are watching crying breakfast friends, and Amethyst seemed so... down? Almost like she feels guilty. It seems if the fusion wasn't fully consentual. Like Garnet scared Amethyst into fusion. Seems a liiiiiittle hypocrytical, no? Anyway it just made me sad to see Amethyst so unhappy about that fusion.
That is true, and you can definitely interperate the episode like that. I think there's another way to intereperate it too - when Garnet found out what Pearl was doing, Amythest kinnd of sympathized with pearl, saying "When we fuse with you, we feel stronger". She could be feeling down because she herself knows why Pearl did what she did, and is a little guilty of having the same desire to feel stronger with Garnet.