Using David's Daughter Tamar to Defend Ash Wednesday?

It's no surprise at all to me that Roman Catholic apologists say a lot of illogical stuff.  After all, they are simply cherry picking mostly from Scriptures.  Some have decided to use 2 Samuel 13's scandalous incest story between a half-brother and a half-sister where Amnon the firstborn of David tried to rape Tamar. One question was when we read of Tamar, again the Ash Wednesday argument still falls flat for this reason- can they really justify it?  To be honest this "Kuya Adviser" guy is really very good in taking things out of context as much as his most infamous opponents the ADD and the INC.

If we read it, Tamar mourned because she was harassed by her half-brother Amnon who developed an incestuous desire over her, she even tore part of her garment.  She did not form a cross on her forehead, she laid the ashes on her head out of mourning for what her half-brother Amnon did to her.  It was not a sign of mourning for sin either.  Just remember, Ahab also did the sackcloth and ashes thing but it wasn't true repentance.  It's a problem that many Catholics receive their ash marks on Ash Wednesday, pretend to be repentant but in reality, they are just putting a whole show to deceive people around them.

Really, I want to question the credibility of the CFD in the claims they make, at the same time I don't want to argue with them either.  In fact, the CFDs have tried every last cherry picking like the mitre argument to defend the attire of their priests, the ark of the covenant argument to justify the Black Nazarene and the list goes on.  In fact they insert fables into Scripture which is just as bad as the now questionable book "The Two Babylons" which should not be a good book to debunk Roman Catholicism because of its illogical arguments.