I cant grieve to my friends, dont know what to do?

My grandad died 3 weeks ago suddenly and my grandma is dying from throat cancer and really bad dementia (doubt she recognises who i am anymore). My boyfriend who i loved also decided that we should break up 2 weeks ago so everything is all happening at once to me. I usually find comfort in talking to my friends but feel i cant say anything because my friends mum died 5 years ago and my other friend recently lost her disabled sister tragically. i therefore feel guilty and selfish to talk about grief and loss with them as theyve surely experienced worse than me but i dont know how else to cope?