While I can understand why it can feel like something controlling, but it is really not imo, that is just basic trust and comittment, Kon is not blind, Ai started getting weirder and distant after she took off the symbol of her love to her ex, someone she was ready to die with, so much she meant for her, she tried to ask for something that can put her mind at ease, to extinguish the dread that is rising in her heart, but Ai refused to block and delete her contact with that same ex, to do that is to show that she is commited to Kon, and won't just go cheat on her if Kaede give her one call, Ai already gone on a wild goose chase once from simple picture of scenery, to keep contact means to allow that to happen again. Kon was never enough for anyone, she felt like she became enough for Ai, and now she is scared that she will become not enough again. Ai have her own issues, she is not villain by any means and clearly she does not want to hurt Kon, but her actions now left an open heart wound that can and considering what story we read almost absolutely will lead to Kon doing worse things