Hamlet- How Sane is Ophelia's Insanity?

Okay folks, so this afternoon I'd like to discuss the character Ophelia because, common, what is going on there?

After Polonious' death, Ophelia is driven to insanity. During Act IV, she prances around a room, adorned with flowers, and professes her sorrows to the Queen and other characters. At one moment, she even attempts to pass out the imaginary flowers to her fellow audience. Along with this, in the ballad she sings she often refers to "he," or her father that is now dead; however, since Hamlet has set out for England, Ophelia's cries may also be because of her loss of another loved.

In the end, the answer in Ophelia's mind to achieving sanity is to, unfortunately, kill herself by drowning herself in a nearby river.

So the question I ask is, how sane is Ophelia's insanity?

We can clearly see that Ophelia has become loco due to her father's death and how Hamlet was also responsible for this. But how can we, or other characters in the book, declare Ophelia's mental state when almost all of the characters have also themselves become insane? The Queen remarried her husband's brother only ONE month after his passing. Laertes and The King have plotted a death with the most intricate precision, sparring no details.

Is Ophelia actually "insane?" or is just the way that others view her before she proceeded to commit suicide?