The fact you recognise it is the first good move you have made in this thread now ask yourself does the friends ‘no show’ make any difference to life with your lovely mum No, of course not but do you know what it is doing? it’s diverting you from grieving properly, is giving you someone to blame for feeling sad and upset it’s giving you an excuse to prolong your sadness
If you really want to help yourself and help your memories forget the colleagues and the ‘no shows’ accept it happened and can’t be changed and concentrate on making your mums memories good and positive ones
Good luck Seansean buy some lovely flowers and put them by a photo of your mum and think of her, not the negatives of the funeral, remember all the past good moments and let it all go, have a good old cry if that will help
Good luck