One of the things I find in reaching out that one can create excuses as to why they shouldn't. For example that friend might not understand or I don't want to be a burden.
There are a couple of things I've used to get round this.
Ringing a helpline according to your country. In the UK you can use https://www.samaritans.org - As they are free of judgement they are just there to listen. I have used them in times not only in deep despair but just feeling a little down.
https://www.mydepressionteam.com/ has also been useful. You can share your feelings and sometimes writing it down or talking about it means the thoughts aren't rattling around your own head.
wow!! That's very kind of you. You're right, this should help too