If you’re looking for resources around Gender and Sexual Diversity (GSD) and Mental Health, you might find the following documents that I was involved in co-authoring helpful.
These documents were produced as part of my work with the LGB&T partnership. They contain guidelines for practitioners, and for LGBT+ people seeking support.
Also useful are these British Psychological Society guidelines for practitioners working across gender and sexual diversity that we wrote a few years back:
Dominic Davies and I wrote a couple of articles for The Psychotherapist on these issues:
And if you want a lot more detail, check out these two books that Christina Richards and I wrote together: