In that light, I use your arguments because your arguments reverse side heavily depending on gender. No woman is forced (outside of rape) to become pregnant, there was always a choice and it takes two. People keep saying "well the man should have kept it in his pants", but that essentially assumes that the woman is a non-contributor to the initial sex act. But she had a choice as well. There was always a choice. The choice has probability of creating life and in the case of abortion/child support that probability is realized. In the purely theoretical context of divorce from responsibility, if one side is given it (and regardless of how you want to define life or whatever so that people can feel better in the real world about what they are doing, abortion is the extinguishing of life for the current convenience of the one involved) then both sides are given it. If the woman can abort and chooses not to, she cannot force the man to support HER decision.
In a real world application as it would relate to your final statement; if abortion were not legal such that the woman could not abort; then there would be no circumstance other than mutual agreement/contract under which the man could shirk his financial responsibility to the child.