Basically there isn't any....The reason being, is we are all different, we have different relationships with the loved ones we lose.
If I have learnt anything in the last three years, there is no time limit. Do not listen to other people's negativity, about "Getting over it", it is not their grief, its yours.
Walk away from insensitive people and promises they can't or won't keep, I have had to. Even been unfriended on FB and blocked because of my grief. But then it does not bother me, as I do not need that kind of friendship.
There is also a loneliness that comes with grief, you can be surrounded by people, but the loneliness is unbearable at times, especially in the early days.
Grief comes with different emotions, some days are good, some days are sad, some days are filled with anger, doubt and guilt. Some days you will cry buckets and some days you will laugh, but then feel guilty. Even question your own sanity.
How I have got through my grief (still in relatively early stages), is each day, I dedicate at least half an hour, to have "me" time, to reflect and remember. I sought counselling too and that has really helped me come to terms with everything.
My grief, came with a lot of mixed emotions, First I lost my mum in 2016, she was in a Nursing home, felt so much guilt, because I could not be there on the final night as I was caring for my sister.
Then I lost my dad 13 months later, he was ill but basically gave up in the last few months. We had mended our relationship, as it was a very fraught time during mums illness. I was with him at the end and it was peaceful, a veil was thrown over the traumatic times.
Then came the devastating and most heartbreaking grief ~ six weeks after my dad, my beloved little sister, who I cared for, decided to go on her journey. It was is in front of me, they did revive her but we were to lose her again, four days later. I had been her carer for almost six years full time. Completely devastated. Not a day goes past when I do not cry at least once.
So own your grief, don't let anyone take it from you. Be kind to yourself and take one day at a time. I am not sure time is a great healer, but time does soften the hurt.
To grieve, is a continuation of your love for someone who is no longer here in the physical sense, but is always with you in your memories and your heart.
Take care <3