Go. For respect to her and to family, and yourself.
She's human. Consider her generation, how people keep things to themselves. Assume she has regrets of her own. Doing what you can for her and family speaks well of you. Letting old resentment shackle you only deepens the wounds.
If she's coherent and you make contact, wonderful. If not you made an effort and were there for family.
*disclaimer: I'm white so probably don't know what family connections mean.