Why do y'all re-crucify Him every week? Why is He still portrayed on a Roman Cross?
We don't 're-crucify' Him. Of course, we have been down this road countless times with you. You just refuse to believe us. At the Last Supper, Christ pre-presented the one sacrifice, so if they could participate in it ahead of time, why can’t we participate in it after that time?
Frank Sheed summarizes Catholic teaching on the point in
Theology and Sanity:
"There is no new slaying of Christ in the Mass....Yet that it is the Christ who was slain upon Calvary is shown sacramentally by the separate consecration of bread to become His body and wine to become His blood. The essence of the Mass is that Christ is making an offering to the Father of Himself, who was slain for us upon Calvary. The Mass is Calvary, as Christ now offers it to His Father."
'Hebrews teaches the atoning death of Christ was effective for the remission of sins and hence
needed to be offer only once. But this speaks of what theologians call the "objective redemption." It doesn't mean that, since Jesus died for everyone, everyone will get to heaven. (That's universalism.) The merits or the fruits of Christ's death need to be applied to the individual.
When Catholic theologians talk about the Mass being a propitiatory sacrifice for the remission of sins, they mean, among other things, that the objective redemption which Christ's sacrifice on the Cross merited is subjectively applied to the individual through the sacrifice of the Mass.'
"Once for All" | Catholic Answers
As far as your question about depicting Jesus on the cross, why don't you ask Steaver? He does it each time he posts something. His reason for doing so might be very close to mine.