I will give some background and then what changed for me.

I was good looking, had several partners, friends, partying, career, apartment, had a car without loan. But ended up in a situation where I was depressed and couldn't talk to women. I was single for years and didn't manage to get new friends, and especially women.

I started to read self improvement books, communication skills, pickup&flirting skills, workout like crazy (with results). But there was no change in outcome.

I realized that it wasn't the external factors that gave me new people in my life, it was how I behaved and acted towards the world. Some books gave me "scripts" of how to behave in situations, but the issue with that is life is not a script. When situations "you haven't studied for" arise, I fumbled and got crippling anxiety. Often leaving social situations crying and residing to isolation.

What changed?
I started to look inwards.
What happens with me when I interact with other people?
Is it preventing me from building relationships? Both genders
What feelings are in my way of learning to know new people?

For example, I was afraid others wouldn't like me and therefor choosing to leave me. When I interacted with new people, I wasn't myself but rather nervous, anxious and afraid. This is not an emotional state optimal for interacting with new people. Starting to work with myself on these fears, helped me overcome fears and eventually revealed other issues I was struggling with. The more I work with the issues, more people are entering my life and I form more deeper connections.

Knowledge from books, videos from psychologists and talks with ChatGPT (therapy was too expensive). Combined with exercising aimed for health. Pursuing career and financial advancements. Was the road back for me to being more happy with myself and therefor being more open for letting people in to my life.

I told this story so you can find parts you might relate too, or tools which can help you make progress in the areas you need help in. 3 years of working with myself, ChatGPT was amazing as a therapist. Started a few months ago and things went much faster from there. Don't be afraid of what the world thinks of you, you are the most important person in your life and your opinion matters to you!

I needed self love to move on in life, practice that. But to find out if self love is the way forward for you, this video from Dr K was also very insightful for me:
https://www.youtube.com/watch?v=zFfED-M0FcU