I didn't use my Diva postpartum- I would let everything heal and "drain" the usual way until your midwife gives you the ok. Only because it's in there for hours at a time, under suction, and pressing on the walls, etc. I'm not too worried about "early" nookie (I'm a beliver in the "if you're in the mood and feel up to it" philosophy), but nookie is a short-lived adventure as opposed to having your cup in, KWIM?
Tampons and sea sponges are definite no-no's postpartum. The risk of TSS and other postpartum infection is too high to have something "living" up there for a while (the cups are supposedly lower risk for TSS, since they don't absorb- but they still press and suck). You really don't want to risk a childbed fever!
I know postpartum lochia is a drag, but it's part of the package! What about some of the jumbo mama pads? Yuk, but that's the nature of the beast, right?