Heartbroken

Ashley • 29 years old. Wife to Brock. Mommy to Charlotte Jayne, Quinn Adalynn, Wyatt Thomas and Rhett Eugene.
My father, age 53, passed away Saturday the 21st.  He was the captain of our local police department.  He died of a massive heart attack.  I'm really struggling. 
The entire city has pulled together and shown a tremendous amount of support.  The generosity of people has been amazing.  I'm from a large, but very close family.  All of my mom's brothers and sisters and their spouses (mom is one of 7) all came in town and were here instantly to help and have been here all week. 
I'm having an extremely hard time.  My little brother is in chiropractic school in Florida, so once he goes back to school it will be just me and my husband to help my mom. 
Anyone have any advice to help us cope?   I know it'll never be easy and things are gonna flat out suck for a while.  But what can I do for my mom?  Other than just be there.  
My husband has been absolutely amazing and stepped up and taken care of every single thing around the house and taking care of the kids. I've not been around and I just am terrified of hurting our relationship.  I know we took the vows, for better or for worse, but I am scared of losing the two most important men in my life. 
This just sucks and I don't know how to deal with this emotions.  I'm grief stricken, mad, lost, and every other emotion you can think of.