On here no grief is more or less valid than another there isnt a pecking order - because life shows us things are not that straight forward and grief cant be put into boxes and compartments.
I think with a friend we maybe open up more - with family there are always dynamics - you cant easily talk about what a sibling has done to upset you too a parent the same way you can to a friend because the parental instinct is always to defend all their children and to sort it out, because they have the same loyalty to both of you -but with a friend they don't have the same loyalty - they are primarily your friend - not your mum and dads or siblings -or partners friend if that makes sense - you can talk to them without starting a family row - you probably have other things in common -you don't have with siblings or parents - they are around your age they went to school with you -you have the same social time in the same space interests in common -or maybe work together -many of us spend more time with friends than family as we grow up - move out of home and maybe move some distance away as well.
Also maybe age plays a part at some level - much as you love your grandparents and miss them there is is also what we have been programmed to think of as a natural world order - and when the expected order is suddenly out of whack its a shock - it also makes you more aware of your own mortality.
With a partner - there is a different kind of love - but a massive part of that love is based on friendship and a lot of what you miss is that friendship - someone you go places with, do things together talk too about anything spend more time with than your original family.
But its not always the case - you cant stereotype based on anything that can be measured by ticking boxes or labeling people in some kind of priority order - for some their gran /mum/ husband was their best friend as well.
Each person you lose is a different person and each relationship between you and them is different - so how their loss affects you is valid no matter what kind of label is put on the relationship - family /partner/friend because they are your emotions and they cant be lessened because some-one else decides the validity of them based on a one size fits all -system.
Both of you will always miss your friends - in different ways sometimes something will hit hard - and the bad memory's the end of their lives, the way you feel now - some of those triggers we expect - an anniversary or doing something you used to do with them without them others hit you out of the blue maybe a song, or something some-one says or watching kids who are friends playing together -But other times you will smile at something funny you shared - and sometimes you smile and cry at the same time - grief is something we learn to live with rather than get over or move on or any of those cliched things people say - we can move forward - moving on -is a different thing.
If it was a physical injury - say you broke a leg badly - you would expect healing to take time you know you wont be running up any mountains for a long time and people would treat you differently because they can see the plaster and the crutches, They cant see grief or depression or anxiety or anything which goes with grief as easily and so you tend to treat yourself less kindly as well -and be less accepting of the time and process of healing.
Over time with the physical you would learn to walk again but during that time you will fall over - there will be days when you are in agony and others when its better - and eventually you might end up with a limp or an ache every time it rains - but if you want to want to get up that mountain you wont let the ache or the limp stop you from doing it, you will find a way - take a break - or just walk up with a stick to help - trying to do it before most of the healing is done wouldn't be possible and grief is the same -start with the plains then the foothills and be kind too yourselves.