As they said, if you're the only immortal in the world, then it's a curse. All your family and friends will be gone; by the end of the day, there's only you. You can try all things in the world even with a hundred years.
I don't know if you ever gonna reply to this thread. But I want to express my feelings. Immortality is a curse in my opinion. The pain, grief and suffering are like waves coming at you unpredictably, you cannot do anything but trying to survive wave after wave of emotions. There is a widower forum where they discussed the pain of losing your partner, it is very depressing and heart wrenching. The strength that gives them the will not to follow their past partner is the awareness of death will eventually come, and they can actually be one with their loved ones again. Being immortal means that you can never die, you will live with the pain that you have lost so many parts of your heart because your loved ones all passed away. It is fine if immortality is a commonly used device in cultivation novels. Readers are also not fully aware of the deeper part of this since the cultivation novels rarely touch the deeper meaning of immortality and loss. However, CN romance novels are obsessed with the kind of love relationship between immortal being x mortal person, I can never truly enjoy such tragedy. The endings are usually either the couple become immortals themselves (honestly best ending IMO), or after the mortal dies, the immortal one sealed/buried themselves to be with their lover (tragically beautiful, but I hate it). What makes me mad with this kind of ending is that readers will never know if the immortal is truly "dead" or not, if you are dead, at least you know you can follow your loved ones. But if not, the immortal person is basically living a Schrodinger's life. At this point, I hope that being buried or sealing off means that they are dead (body may still living, but there is no consciousness, no senses, no perception, or no "soul" inside the body) since my heart cannot withstand the tragedy of living alone.