If it's just you being immortal, loss of all family, and friends, and loss of new friends, rinse repeat forever. Eventualdieyoull watch society collapse and regrow (possibly), and the planet will die. Immortality is forever after all. Then you're left alone on a deserted dead planet. Electronics you have will eventually break and fade away to time. The sun will grow and die off, and it'll burn because you're immortal but still stuck on a planet that'll get enveloped, eventually. Living forever would be terrible unless it was forever until you died of something physical, just not age and illness.