Socially awkward mother

I am not sure that I should bring this up to my mother, but it breaks my heart to see her struggle and lack attention that she so badly craves. She is socially awkward in the sense that she pays little attention to others' stories, frequently interrupts to tell her own exaggerated stories, and generally just doesn't "read" the room she's in. I love my mother and while it can be frustrating, I understand that she is craving attention and since my father passed, my other siblings have all but cut her out and I am the only one she feels that she has to turn to. She talks incessantly and has to be the center of attention...which, of course, turns most people off, thereby making her NOT the center of attention. Holidays with my girlfriend's family have become extremely awkward because nobody wants to get "trapped" with her, yet I am not about to let her spend those times alone.

I have tried, in prior years, to address some of this and have tried to help her understand that my siblings frustration with her stems from her not listening to them. She says she understands, but then makes excuses for why she behaves as she does and has made few attempts to try different approaches.

How can I help her without offending her or making matters worse?