I definitely agree with the comments on here the stress that makeup is not for others, it's for one's self. The fact that you're introducing your daughter to makeup while educating her about how makeup is a creative outlet and that true beauty is not synonymous with makeup is very integral to her social and emotional development. I think it's a great lesson and experience for your daughter, simply because it facilitates at a young age that makeup and beauty is a choice and not a "you must do this because you're a female" type of thing. In my opinion, I think your SO came at this at the wrong angle. He should have sat down with you and said "What are we, as parents, going to agree on teaching our daughter when it comes to self confidence and gender roles?" instead of what came out of his mouth instead. Now, that doesn't excuse his insensitivity, because you have every right to feel upset. I would have reacted the same way as you did. My Mum taught me the same way that you are teaching your daughter about makeup. She would allow me to wear small amounts of eyeshadow and a little bit of fun lipstick, but would always stress that it was my choice and not anyone else's, and that I was pretty with or without it. With that being said, my Dad HATED that I wore makeup- absolutely hated it. Said it was ridiculous and I didn't need it and it wasn't necessary. Despite his poor delivery of how he felt at the time, we spoke just recently about it and he said that he was trying to protect me and didn't know how to handle me growing up. Makeup, to him, was signifying my becoming as a woman.

Bottom line, I don't think you're doing anything wrong by wearing makeup yourself and teaching your daughter about it at a young age before things like puberty, peer pressure and the dreaded land of high school comes into her life and bombards her with these things. If you decide to discuss this with your SO, I would phrase it that way. I hope this is helpful for you. Wishing you all the best xo