That looks like maybe a bottle fly. Googling indicates the adults last 50 to 60 days^1^.

^1^ https://www.researchgate.net/publication/344275278_Longevity_of_Adult_Lucilia_eximia_WiedemannDiptera_Calliphoridae_Under_Standard_Conditions

Those are pieces of an onyx chess set. I used to have that exact set. Here's an example from ebay: https://www.ebay.com/itm/276268677793?itmmeta=01HQGDMT5HNWBF8YNWTDN1Q1D5

Your disability is not your fault.