I can understand how awful you feel, especially as you are blaming yourself as well as feeling so sad. Can I just make a suggestion that might possibly help a bit? Could you get an exercise book and as you think of each photo, give a page for each one, and then write down all you can remember from the actual picture,who was in the picture besides your mum, and add on what you know of the occasion , such as family party or christmas special gift. If it was in colour, put that and the style , or pattern of the dress she was wearing. For any time you were there you might add something about what you and she did etc
You may feel that this is adding to your sadness and hurt, which it may do for now, but whilst they are fresh in your memory you can write it all down and connect them to family occasions. Then over time you will still have those reminders, and other memories may pop up. While you are doing this perhaps you might remember some friends who might have been at some of those occasions, or was there ever a time that she might have been a prizewinner in a local show , where there might have been a picture in the local paper? If you think that is a possibility you might be able to search through that papers archives.
This may seem like only crumbs, but can be better than nothing. I have a very tatty old green piece of writing paper , which has a recipe that my mother wrote out for me when I lived abroad, more than 50 years ago. It was for one of her own special things , which as a diabetic I never make these days but it is treasured by me. Have you been able to find even one or two pictures or cards etc, which you can hold on to.? So again, as you remember them write down about those little articles, the little fairing won at the fair, the menu card from that special time.
This will not all come back to you at once. I have been flooded and a close friend was flooded so deeply she had to retreat to the upstairs, and everything from the ground floor had to go. We both found that although the obvious things such as furniture were easy to claim for and deal with, it was as you say, photos and precious books etc, and many things only occur as you realize that of course the christmas tree lights and decorations bought over the years have gone etc. As we had a tradition of adding one ornament each year to the christmas tree, and still put ancient crackers made by my son as a young child, it wasnt the cost of the items but what they represented. So I did make a list of all I could remember , especially things from when we were abroad. I hardly ever look at that list these days but the year after it all happened I found it something worth looking at.
Most importantly you still have your memories of her, which will stay with you. You might also have old photos of yourself and you could use them to remember where and what your mum was doing when they were taken. I do hope that whatever you decide to do, you are able to feel less upset over time, and perhaps writing about some of those photos will ensure that you are helped to remember them in the future.