Sorry if not allowed then please delete

Hey everyone, so like the title says, I need some advice. The thing is, I love SPH, I opened up about it to my girl some time ago back. But the problem is she says she doesn’t want to hurt my feelings or be mean, I’ve given her the go ahead several time to be mean, I’m ok with it. I’ve even initiated some things for her to say and asked her if she preferred me or a much bigger dildo and things like that, I’ve also got her to talk about her exs and how I compared while we were doing stuff, just in a desperate attempt to get called small. But no matter what I say or how much I tell her it’s ok, she is still hesitant to say stuff or be “mean”. So please if anyone has any tips or pointers for me to try and get her to open up, please tell me. Thanks