There are a handful of solipsism threads here at the Nexus, and you can feel free to search those to see some of the in-depth conversations we've had about the matter, but something I would just like to add here is, let's assume it's true, and you are the "only player". If so, so what? You can't be conscious of your creation, or you would know everything about it along with all the rules. So this part of yourself that has created the universe of which you're the only player is a part of yourself that remains perpetually unconscious to you. In this experience here, you're not alone. You can have beautiful (and terrible) interactions with human beings that allow you to feel emotion and experience life. To get caught up in the anxiety of being the only one (in what is IMO an unlikely scenario) is to let your fears get the best of you.