Yes it is normal a lot of people here will tell you its like a roller coaster ride,it does smooth out over time,but I once burst into tears over hearing a Christmas Carroll my mum used to play on the piano 11 years after I lost her,which I was totally not expecting,so even when it seems to have smoothed out it can suddenly knock you sideways again in a very unpredictable way.work is a distraction but a distraction can not last all the time,much as we want to not be grieving we cannot just put it to one side all the time.I think the acceptance part of grief is accepting that it will always be part of us.That doesn't mean it will always be overwhelming or that your lives will always feel so bad as they do now though.