Why are some people insensitive about someone grieving or going though a rough time?

It was hurtful for my brother and I when our mother got diagnosed with strange four breast cancer last October. We had lots of support but when she passed like after her memorial I’ve gotten roasted and people joking with me. I mean I know they mean well and try to lighten up the mood but we had JUST lost our mom a week in a half. She passed this past January. One of my uncles roasted me about me looking like my dad is a problem. He said my brother is a split image of our mom (which is true) and he said he didn’t know about me and if I look like my dad it’s a problem. I wanted to call him out but I didn’t want to cause a scene. He HAD to joke at a time like this. He understands loosing a mother (grandma passed almost 10 years ago) but roasting me wasn’t the best time. Then a friend of mine called me motherless and she understands about losing a mother. I don’t think she was being mean, but I didn’t need to hear that. Sick of people trying to get me to be the same person I was before. I got sensitive when people try to joke with me. I mean HELLO it wasn’t the best time to joke when we JUST lost our mother. I wasn’t trying to be moody but losing a mother is traumatizing. I don’t mind people making me laugh and I do love it. I know it doesn’t sound like they were being mean but I needed to vent. Next month it will be nine months since she’s been gone and I’m STILL hurting. Fuck grief.
Why are some people insensitive about someone grieving or going though a rough time?
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