I think I feel embarrassed because it's associated with acting like a baby (which I consider a pretty weird taboo thing to do sexually) as well as the mothering being like a fake incestual fantasy, I don't know. It scares me to imagine her imagining me in her lap nursing on her, and cringing at the possibility that she's internally cringing at the mental image, like you can't avoid picturing it if someone tells you that. Is she going to cover up? be more aware if I accidentally glance at her chest?

The closest I could imagine hinting at it would be something like "cuddling, being mothered and nurtured in a sexual or sensual way."
I wouldn't want to give her a poem about it, but I'll try writing one for myself because that's a good idea for exploring my feelings Parva.