That is great you declined his offer, well done. You're setting a high standard for yourself.
And really good that you expressed that what you're doing is enough. If you did less than half of what you're doing it would still be enough because you've had your heart broken so you need a lot of time to get your emotional energy back.
I can imagine the walk and talk about codependency with your friend would be draining! For me even hearing the word "codependency" is draining! I think a lot of people on here are attaching themselves too much to that label. Everyone gets codependent in a relationship, hence it's a relationship. Sometimes the balance is heavily uneven and that's when you get driven mad. But we never asked to fall in love with people with mental health issues. I see it as a spiritual lesson about growth. If you can learn from it, great, but lose the label. You're only a codendoent when you're actively being one. Right now you're not!
And you won't be again! Because you've learned all this new stuff.
Funny how clearly I see now in regards to "codependency". Upon observation of pretty much everyone I know, turns out all they all do codependent things! Lol... I think it's pandemic in society. And we really ought to laugh about it. At least we know how to deal with it now when we get that "I want to fix him" feeling... We can say, "oh, I've been here before... Maybe now is a good time to get centred". And voila we just broke a pattern! And we will continue to be 'work-in-progresses' as we navigate through life since life always throw challenges and curve balls. Life is one big lesson!
I didn't even finish the book "codepdencey no more" as it was too harsh I felt. And my heart didn't need that right after a break up.
But I took what I needed from it. I. E. Detach and take care of myself when I feel myself getting anxious over someone else's problems.
I think the fesrfulness you feel of not following guidelines, is an indication of anxiety. Which is a fearfulness of uncertainty... All very natural since you just broke up with someone who really hurt you and scared you. And the rejection hurts majorly I get that complete and relate. Your threat system was attacked, you no longer felt safe in your own decisions, so it's no wonder your anxiety is high. That'll all relax soon though. The more soothing things you do for yourself the nicer you're going to feel... Simple soothing things. And rejecting that guy who asked you out showed self respect and self confidence.. You're doing better than you know Glenjo!
Also in regards to the guy you were with... If you feel like writing him a letter, you should just follow your heart. Worst case scenario is that he ignores and rejects you but at least you'll have a chance to speak to him from a place of calm and love. And you'll be better equipped to handle how he responds or doesn't respond. Maybe your soul will want that at some point. I also believe that what's for you won't pass you.