I may be able to help with your search for understanding.
There is no additional sacrifice, we participate in by a proclimation of the one sacrifice of Jesus. We follow his command: “Do this in remembrance of me” and His words “For as often as you eat this bread and drink the cup, you proclaim the death of the Lord until he comes.”
[1 Cor 11:24,26]
Some non-Catholics seem to think as you do, that Catholics are offering additional (and what would of course be unnecessary) sacrifices. Hopefully my explanation above shows that this is just a misunderstanding.
I understand that some non-Catholics disagree with Catholic teaching, but I’d rather someone disagree with what I *actually * believe rather than what they mistakingly think I believe.
Cheers, my brother!!
(to the Holy Spirit I pray for guidance and understanding)