That's what therapists are trained for. Sometimes a support group can be helpful to.
For me it started with "My dad left the family when I was seven" and ended with "The physical and emotional abuse I've been subjected to by family and school is having detrimental effects on my abilities to create functional relationships with the people I love" some four years later.
Well, that is very specifically me. You have a different place to start. It could be as easy as "I'm not happy". It doesn't have to be about where to start, that's just an opener to a conversation.
For me it started with "My dad left the family when I was seven" and ended with "The physical and emotional abuse I've been subjected to by family and school is having detrimental effects on my abilities to create functional relationships with the people I love" some four years later.