God Stuff: Grace and Truth

"The Word...came from the Father full of Grace and Truth" John 1:14

Been thinking about Grace and Truth again...
Thought that I had it figured out to a degree - then it overwhelms me again.

I can't figure out:
Do Grace and Truth coexist as separate but side-by-side entities like 'tweedle dee' and 'tweedle dum'?
Are they both two sides of the same coin?
Is Grace infinitely bigger than Truth or visa versa?

It may seem irrelevant but in practical terms I guess if we have some understanding of this then we will know when to say "No - enough is enough - and stand firm on issues" and when to say "I'll keep giving/relenting/tolerating/I'll keep my mouth shut even though I don't agree with you/you dont deserve it".

My head hurts. Off to Bed.