You're not pathetic, many people experience this anxiety. Opening up to someone, especially pretty much a stranger, can be very hard.
I also experienced it, I could never tell anyone about it. Friends, therapists, doctors. It was just like something took away my ability to talk when I wanted to say anything.
The first time I ever did tell a doctor about it, it was only because I was directly asked if I have thoughts about death. Well a simple yes or no is easier to say than explaining the whole thing. Still very hard, though.
What I can suggest that may help you:
- if you have someone close to you (friend/family member) who can come to the appointment with you, you can ask them to tell the doctor that they know about your suicidal ideation
- you can suggest that you don't really see a future for yourself,
Basically lead to a situation when the doctor asks more directly. Maybe that will be easier. Other than that you can write it, like others said.
Good luck, I believe you can try to get help again.