Dealing with loss

H • 26, single

My grandfather passed away recently and I don't really know how to deal with it. It was really unexpected. He was healthy and happy, he used to come over for dinner every Wednesday and I never thought the day would come so soon. Most times I think I'm over it, but then it hits me and I find myself desperately wishing that he would just come back. I wish I could have talked to him one more time and had one last conversation. He was so wise and I had so much to learn from him. I guess his passing has opened up some fears that I don't like the thought of. I have never witnessed the passing of a loved one before his, so it kinda reminds me that I will have to deal with more throughout my life. I don't think I am prepared for that. I just wish I could stay with everyone I love, forever. I'm sorry, I probably sound irrational af. I would greatly appreciate advice on how to deal with things like these. Thank you for reading this :)