I fear not being able to work again.
As long as this isn't imminent, why fear it? You can just as well fear that the sky will fall down on you. There are many ways to earn one's keep - maintain an open mind when it comes to chances that might come along, but try to keep your thoughts to the presence. It's the only sure thing in the world, anyway.
Again: why fear something as uncertain as that? You don't even know what circumstances will lead to your death; maybe in the minutes before you die, you will
want to be alone. Then all your fears will have been a waste of emotional energy. Celebrate that you live, and that you are not alone right now.
I fear those biscuit cans that go POP when you press a fork on the seem.
No idea what you're talking about, but maybe you should buy a shitload of them, then take a fork, press the seams, and experience the POP as long as it takes to not be afraid of it anymore.
I fear nobody will take care of my wife when I'm gone.
From what I've read of her so far, Morrhigan doesn't seem to need anybody to take care of her. She comes across as an independent, active woman who knows what she wants and how to get it.
And anyway, does she have that fear? Because if she doesn't, why should you? It is her life, her responsibility to take care of herself. It is nice that you want her to be safe and be looked after, but honestly? Take care of yourself, and give her the freedom to do so as well, with or without you.
Why? Is it the water you fear, or something that might be in it, or the depth?
I fear I'll never get into good shape again.
Now that's just an excuse to be lazy! You know exactly what to do to get into a better shape than you are in now, so fucking do it already! Just make sure that you have a realistic view on what's possible regarding your health status, time schedule, age, and motivation, and set your goals accordingly.
I fear those people who fill balloons in party stores.
Now that's a fear I understand! Creepy buggers, all of 'em!