Heart broken

My grandma passed away last August. I had a sister that only lived 2 weeks die last April (2 weeks isn't long, but still, she was my sister and its hard). I just can't get through this. I have serious mental issues from trying to get through it. My grandmas death was very unexpected. No one saw it coming. She was only 63. I never even got to say goodbye. I don't even remember our last conversation and that kills me! She was my very best friend. She died 3 months before my wedding. I always wanted her to be around my kids when I have them. I just don't know how to cop with this loss. I cry all the time. I hate that I also can't feel her here with me. I always thought I'd be able feel her when she passed, but I don't. I don't know what to do anymore. I'm a mental and emotional wreck even though I don't let anyone see it. I'm just so torn to pieces!! 💔😭