It depends on the person. Grieving is very individual process, and it can be different for each person how severe and how long we are grieving. For someone it is a year, for someone two years... for others it can be whole life or many years. But It does not mean that you need to suffer the rest of your life.
I think the most important thing is to give a time for yourself and your grieving process. Don’t rush anything and don’t expect to get a quick immediate relief. But at the same time remember that there are things that can help to ease these emotional pains related to grieving. The things that helped for me was mindfulness meditations and visiting psychotherapist.
I think one of the most important thing is to not staying alone with your emotions, reach for support and help. It can be close friend, therapist or maybe some group support from other people who are facing the grief process. For myself, the therapy really helped, because the therapist is a stable support, on which you can rely on. In a therapy once or twice in a week you can visit your therapist and vent out all your emotions.
In the hardest moments of grieving I let myself cry out, and after that I meditated, it helped me to grounding back in the present moment and restored me to focus on other life duties that I had. Later, a three months after I lost my loved person, I started to write letters, not much, just a few special ones, and even now, sometimes I write letters, for example I wrote letter in last Christmas. Of course sometimes when memories shows up, there are still tears, and it is naturally that you want to cry when you remember this person, but visiting therapy, crying out, meditating, it all helped for me. Also reading materials about grieving helped me and gave additional information about this mental state, for example Verywellhealth.com have a nice reading materials about grieving process.
Also, I think it is important to not forget your hobbies, your things that you loved and enjoyed before your loss. For example, for me, I really enjoy talking a long walks in sunny days in the wood or sea shore and listening music in my air dots. I encourage you to consider the things that you may enjoy, the things that can help you to get at least any relief and enjoyment.
Best wishes Eddy.