How can I comfort my boyfriend after his mothers death?

His mom was 53 and died of a heart attack, with no warning. He has never been great about opening up to dealing with his emotions, and seems to be concentrating on material things, and worrying about his dad... and I'm worried it just hasn't hit him yet what happened, it's only been a few days. I am not pushing him to talk about it or anything of that nature, but I guess I just have a hard time being strong for him because I am hurting too, and crying seems to be my way to deal with her death. She was going to help me and him plant a garden over the weekend, and tonight we are going to plant it in her memory and I'm worried this will bring up some of those emotions. He has been a little snappy, but I know it's because he is sad. Any advice would be greatly appreciated as we still have a lot of things to go through and do b/c she owned a seamstress shop at his parents home, have many customers to call and inform, and tons of things to try and find and sort through.. Thank You. I guess I need some advice on how to deal with this too. SHe was a wonderful woman with a zest for life, and I just can't believe she's not here anymore, and won't be able to be at our wedding (we've been together 6 yrs. & lived together for 4 1/2) and all of those things you don't think about until things like this happen