Can loss of loved ones mentally destroy a person?
It’s completely up to the personality and the state of environment the person is in, if the person who is mourning is not mentally strong or the emotions take over their entire thinking process/character than the human brain can easily break. Although the brain may seem strong, it’s just a paper thin difference from insanity, your imagination can take the best of you quite easily if you are mentally sensitive, and may need to seek professional help. To answer your question directly, yes, it is completely possible.
Yes and no. Depends on how that person affected you in the first place. But the initial loss is always heartbreaking. No doubt about it. But with time every wound heals and so too the loss of a loved one will not be felt strongly subsequently. What is important is to take specially care of oneself when the loss happens as this is the most vulnerable time for any real damage to set in. The loss of a loved one leaves one insecure and very very lonely. That is why people move on and find that someone special again as it is human nature to love and seek love in return.