Just musing, I'm like a spare tyre to someone and I'm not putting myself down. Think about it, when you've done what you should've done, and could have done, and couldn't do more than what you've done, you retreat into the background and kind of fade away. That's how I feel now. A spare tyre.
Is the spare tyre important? It is! Though it is not in used, it has to be there. No car goes around without a spare tyre in its boot! It's unthinkable, it's dangerous. Though it is a spare tyre, and is not the one running, having it in its place gives the driver a great deal of confidence. If a tyre gets punctured, there's a spare one in the boot! A spare tyre gives a lot of psychological comfort and support, and no car owner can go without it.
So, I'm a spare tyre, I'm always here for you, you can't see me, you don't sense me, you're not even aware of my existence sometimes, but I'm here for you, and when you have a flat tyre, you'll remember me, and I will serve you faithfully. :)