Hope,
Talk to your sister any time you feel like it, if she is ok with this. There is nothing wrong with that. There is no rule that says its time to stop talking. Its been 4 yrs and I havent stopped talkin about my mom here, although just not as often as it used to be.
You are in the very early days of your grief so dont rush yourself. I think that we need others to talk with about that loved one... I found that I needed and wanted to be around my family more than ever, just to be in the same room with them, just to hear their southern accent like my moms, just to see people who resemble my mothers looks, and just so we can once in awhile say something like "if mom were here she'd do this or say that". I wish I had that but I didnt. You do so do it.
Bottem line, ,, whatever you need, do it. No one is gonna help you through your grief more than you are going to help yourself through it. You have to reach out and let people know what you want or need and talk all ya want about mom to anyone and everyone who will listen, including us here. I once asked a therapist how long I was supposed to talk about something. And his answer was "as long as it takes." "You'll know you're done talking when you dont need to talk about it anymore". Sometimes you'll feel the need to tell the same story over and over again. Thats ok too. Just talk and share. Thats what we're all here for. And hopefully thats what your sister will be comfortable with too. I'm hoping that by you talking and sharing will help bring her out of her shell to talk more too.
I can remember 6 mos after mom died, my gma died. And all of us were together for the first time since mom died. But no one said one word about mom. It was as if she was gone and forgotten. I was furiously hurt but never said anything. I wanted and needed to share stories of what mom did or said, the good times, when I was with my family. But I dont have the comfortable family situation to do that. I hope you do. And if you do, let this be a time to draw you closer to each other.
hugs,
lauren