This is a time when it may feel like the world is on your shoulders. The objects that you receive from a decedent relative don't replace the human who is lost, and the loneliness that results from losing those around you. Could this be the reason that you're feeling this way?
Certainly, I can't answer that... but it's important to find someone with whom you can spend time and talk, face-to-face. This is not something that you should face by yourself. You know it well yourself - this can be overwhelming.
Of course, we're here for you, and will listen and talk. But find someone in person to do so, as well. There's no replacement for the real deal.
I continue to wish you the strength to get through this difficult time and find happier, shinier days ahead. There will be good days.