Feeling down...

I'm having my baby shower today and two of my friends wont make it because they have both lost children in pregnancy within the last year and say they just cant bare to be at my baby shower. I kinda feel bad for even having one now and not sure how I'm supposed to feel I understand why there not coming but would have really wanted them to celebrate this with me. I'm at a loss on what I'm feeling and how I should feel. Has anyone experienced something similar? I feel like I shouldn't be happy today I'm so emotional about it.