. . . et cum Spiritu Tuo!
I hear your pain. I have experienced some of the same in some Catholic churches. I can also tell you I have set in a Baptist church where the pastor is well aware of un-married, co-habitating couples in which he gives communion.
Why so many liberal Catholics? Same reason their are so many liberal Baptist, Methodist, Presbyterians. Liberal seminaries. However, much weeding out has been taking place over the last few years in Catholic seminaries. Kinda like what happened within the SBC a few years back. Praise God!