It Depends
I often compare emotional strength to physical strength; Some adversity is good.
To build an immune system, you need to get sick, so your body learns to fight it.
To build muscle, you need to damage it, and then allow it to grow back stronger.
When you handle rough material, like wood or rope, your skin thickens and builds callouses.
Same with emotion. You need to feel that pain and cry for a while, before you get stronger.
But, this only works to a certain degree.
When sickness overwhelms the body, toughing it out can be disastrous.
Exercise too hard, and you can do permanent damage.
And no callous can stand up to blades or shards of glass.
Learn not to cry over spilled milk, and you’re stronger. But hold it in when real shit happens, then you’re doing damage.