The Moon holds faithful to the coast...

[TranquillityBase]

Thanks again!

For the first two lines, I just switched the two objects around. Would

The Moon holds the tide faithful
to the coast, yet Romeo calls her envious....

work as well?

In a way, I'd rather see your first line stay and drop tide, however, your solution above would work as well.  Would give it a fuller meaning.

I just love that first line so much I hate to see it go.