I quoted scripture in which I don't see any allowance for a divorced person to remarry. Some might argue that remarriage could be inferred. What I see as common between Jesus' and Paul's teaching is not that divorce is never allowed but that allowance for remarriage after divorce is not articulated in scripture.
A problem w/in Christianity is that Believers pick and choose scriptures to follow and ignore the rest. You mention the term 'legalistic'. Are there absolutes in Christian doctrine or is everything open to negation through grace and personal interpretation?
I'm not a judge. Divorced and remarried Christians persons answer to the Lord.
Maybe a better question to ask is: "Are preachers preaching the Word regarding divorce and remarriage or are they compromising to not offend and lose congregants?" For too many, I believe it's the latter.
Matthew 19:9 says: I say to you, whoever divorces his wife, except for sexual immorality, and marries another woman commits adultery.
So in the Luke 16:18 one you posted, Jesus seems to be not talking about a scenario of adultery in the marriage (before divorce). But in the Matthew 19:9 one, He's talking about adultery in the marriage being an exception for it being sin to divorce and remarry.
So which Jesus is right? The Luke 16:18 Jesus, or the Matthew 19:9 Jesus? Obviously, both are right because it's one Jesus. So I infer from that logic that Luke 16:18 implies scenario of divorce without adultery. Thus we shouldn't apply Luke 16 for the adultery situation (or we'd be saying that Matthew 19:9 is wrong).
At least, that's how I see it.