To be honest, I don’t see anything specifically anti-Catholic in the post in question. But I can readily see how certain people would try to use it as the basis of an attempted refutation of Catholic beliefs and practices. Whether or not this woman intends for her statement to be considered a criticism of Catholicism (wanting the reader to “fill in the blanks”) is unclear.
If I were to engage this person in a conversation, I would simply point out that (objectively speaking) Catholics would agree to what she has stated. If she then says that Catholic beliefs and practices contradict her position and the Scripture passages she quoted, then I would ask her to explain how. It would then come down to a debate over authentic Catholic teaching verses misunderstandings of Catholic teaching. It may also be a debate over a correct interpretation of Scripture. Catholic doctrines do not contradict Scripture, but only contradict certain people’s personal interpretations of it.
As a side note on her abstinence comment, if she is referring to such things as fasting, she is correct. After all, such acts, in and of themselves, do “fall short” if they are not sincerely incorporated into our relationship with God. If that is all that this woman is trying to say, then that is, in my opinion, all well and good.
But if she goes further and suggests that fasting in general has no spiritual merit, or that Catholics are wrong to fast, then that would be a different story. Fasting, when done with the proper attitude and intention, is an important aspect of Christianity, as we can readily see in the following instructions from Jesus…
“And when you fast, do not look dismal, like the hypocrites, for they disfigure their faces that their fasting may be seen by men. Truly, I say to you, they have received their reward. But when you fast, anoint your head and wash your face, that your fasting may not be seen by men but by your Father who is in secret; and your Father who sees in secret will reward you.” (Matthew 6:16-18, RSV)
Notice that Jesus does not say, “if you fast” but rather, “when you fast”. It is an expectation, not a suggestion. In this passage he also describes the proper attitude to have when fasting (i.e., don’t fast as a way to get attention and praise from others) and tells us that God will reward us for having fasted.
Then the disciples of John came to him, saying, “Why do we and the Pharisees fast, but your disciples do not fast?” And Jesus said to them, "Can the wedding guests mourn as long as the bridegroom is with them? The days will come, when the bridegroom is taken away from them, and then they will fast. (Matthew 9:14-15, RSV, emphasis added)
Once again, Jesus ascribes fasting to the Church. This is born out in the Acts of the Apostles:
While they were worshiping the Lord and fasting, the Holy Spirit said, “Set apart for me Barnabas and Saul for the work to which I have called them.” Then after fasting and praying they laid their hands on them and sent them off. (Acts 13:2-3, RSV)
And when they had appointed elders for them in every church, with prayer and fasting they committed them to the Lord in whom they believed. (Acts 14:23, RSV)
And, of course, it is worth pointing out that Jesus, himself, fasted in the desert.
But before presenting any of this biblical material to her as an intended rebuttal of her statement, it would be good to first have her clarify what she means when saying, “Abstinence falls short.” Is she actually referring to fasting? And, if so, is she simply saying that fasting in and of itself is not a substitute for having an authentic relationship with Christ? If that is her intention for making the post you quoted, then she is on the same page with Catholic teaching.
The problem at hand is that she used the phrase, “falls short”, and that is a fairly vague term. It would be helpful if she clarified what she means by that term. After all, in light of the material I’ve presented here, fasting can be said to “fall short” or not to “fall short”, depending on the circumstances (as Jesus explained in Matthew 6:16-18).