> What if you were in a simulation so that it seemed like you were doing all these things with other people, but you knew that you are in a simulation all alone? Would these things still have meaning? Would the experience be worthwhile?

If it is in fact a perfect simulation, and you as the actor in said simulation cannot detect a tear in the fabric of the simulated reality, you will, in due time, repress any prior knowledge of said previous "reality" by integrating it with your reality i.e. rationalizing it as a dream. As there would not be any discernible difference between being real and feeling real, any worthwhile experience would, by definition, be worthwhile.