Even though a completed couple are able to love as long as they are too old, they can't escape the rule. Between both of them, their death will set them apart. It's no matter if he/she lives or passed away. It's mainly important whether they have had enough for their good memory during living togehter or not. Al least, they can easily smile when recalling their good memory.
It's no matter if you still cry at the moment. Life is simply going on like this. You have a bad day. You have a good day. You have a nothing day. Happiness cannot take all your time. Unhappiness cannot take all your time either. Happiness comes and goes. Unhappiness comes and goes as well.