Hi Jekka. Welcome to Psych Central. I am sorry for the sad news about your grandmother.
If you can it is good to talk to your grandmother and tell her about all the wonderful times you have shared while she is living. If that is not possible, even writing those wonderful memories for which you are grateful can start the healing process. Grieving is different for everyone so accepting yourself and your grief is an important part of the healing process.
These articles or support sites may be of interest
Grief and Loss Resources
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