Untill i met my current boyfriend I always had issues with sex and being clothesless when on my period, but my boyfriend now was just amazing about it, he sees nothing wrong with me or it, and like DowntownAmber we just go for it.
I find though, that because my hormones are *all* over the place when I'm on my period, we have to be especially careful during any scenes, because I sometimes find it hard to differentiate between whats in a scene and is just being said for my enjoyment, and whats actually being meant. eg humiliation, normally i can walk away from a scene after a cuddle and a chat and be fine with it, its not a knock to my self esteem, but when im on my period... i can really take it to heart.
Not that that was really relevant.
Why not have some rituals or do some roleplay which doesnt culminate in sex?