I used the phrase 'loaded to the gunwales' yesterday, which was a household phrase when I grew up. We always were an unusual family.
But thank goodness for spell-check. As it's not a figure of speech that I'd generally use in writing, I'd assumed that it might be spelt as it's spoken, and typed 'loaded to the gunnels'. I know you wouldn't have made this mistake, well, would you?
A gunnel, as you'll well know, is a type of elongated fish. A Sally Gunnell on the other hand is a British former 400m hurdles Olympic champion and subsequently TV presenter in the UK.
A 'gunwale' on the other hand is something else altogether. Like many English phrases it dates back to sailing days. A gunwale or, formerly, a 'gun wale' was a reinforced part of the hull of a fighting ship in the shape of a ridge placed at and around the level of the gun deck: placed there so your vessel wouldn't fall to pieces every time you shot your cannon.
The cannons on a ship protruded through gun ports (holes in the gunwale, I guess) and if you wanted to stay afloat it was obviously more than sensible to keep these above the waterline.
Loading a ship to the gunwales, therefore, suggests piling it with such an enormous amount of cargo that it's only just able to stay afloat.
One more keg of rum, one more chest of treasure, and the whole thing could be on its way to Davey Jones' locker, swimming with the gunnels perhaps.
To mix our metaphors, it's rather like the straw that broke the camel's back: that one last addition that tips a situation from Yes to No. From Go to Stop.
I'm pretty sure we all have a gunwale. I'm fairly certain we all have a limit beyond which we move from being able to cope to being unable to, and it's undeniably important to know where your gun ports are: try to be aware of when enough's enough. This way you'll rest when you're exhausted. You'll walk away when you're about to explode. You'll open up to someone before dark thoughts consume you.
So the next time things threaten to get a bit too much, try to make a few changes before the water gets too close to your gunwales (so to speak).