Voluntary abstinence during fertile periods is no different from contraception.
Not to preach NFP, but I have to call you out on your error here. Periodic abstinence during fertile periods is NOT the same as contraception. Contraception is the deliberate frustration of the procreative aspect of the marriage act. It is separating the unitive and procreative aspects, by deliberately and artificially
removing the procreative aspect out of the equation. That is, by using chemicals, barriers, etc. By contraception, the husband and wife don't give/receive all they should in the act -- they positively exclude the possibility of children.
That is not true when the act is done in a completely natural and normal manner, with no man-made artifices intervening.
You can be against NFP, but let's not exaggerate. We are bound by truth here. If sticking with the truth makes NFP seem or sound permissible -- then *gasp* maybe it is! It wouldn't be the end of the world. What's more important is to NEVER deny a single truth.