How long does it take for one to get over the recent death of one's mother?

I have a friend thats in his late 30s his mom has been sick and hospitalized. She recently passed some weeks ago. I used to hear from him at least 2–3 times a week, but since his tragic experience i havent heard from him. Last i heard from him after her death he said he still cant believe shes gone. he hasnt called me, i tried to call him and i get no answer. i try to be supportive and give him his space so i text him from time to time and let him know he’s in my heart and on my mind and let him know i love him. it’s bothering me because he was soo close to her and he’s such a big, strong man i figured he would have it under control. i drove by his moms house and saw him sitting on HER porch by himself. what do i need to expect in the future and how can i help confort him without bringing her up and being a nuisance to him. i wouldnt want him to snap out. besides i lost my mom when i was 11. i can relate, but im long over her death.