Struggling with Loneliness and Isolation

Today I am finding it really hard to cope. I'm struggling a lot here lately. There's always something that triggers me and no matter what I do, I can't shake this feeling. I'm alone, no family, no friends, kids are moved out starting their own life, husband passed away, no calls or texts from anyone. I try to reach out but nobody cares, no response back from anyone. I feel myself giving up. The silence is killing me.