How good is he, if he doesn't care about making you feel loved? That would erase any sense of 'guilt' I had about leaving.

And in any case, staying or leaving a relationship isn't any moral judgement of character. It's simply something that does or doesn't happen based on compatibility, as you said. You are the one somehow conflating it with a moral judgement and making yourself feel guilty because of it.

It's condescending to be a reductivist about this, fyi. If you tell anyone that their job is 'just doing x', it's going to come off condescending.

Take that as you want. You can't say 'it's not condescending'. You are being condescending, whether you want to be or not. If you don't want to be, change the way you communicate in the future.

There's a lot of jobs that can be boiled to 'just doing x', but that doesn't make it reality. A server isn't 'just bringing food to the table', just like I don't 'just type words into a computer' as a software engineer.

You are absolutely being reductivistic and it is unhelpful to any other point you are making.

I know you have already said you are going to the wedding, but here is my advice for you as one older woman to a younger:

Assume that if you were invited somewhere, you are wanted there. I know it is easy to worry 'but am I really wanted, is this a pity invite or just a formal thing?' Etc.

But those happen very rarely. More often than not, if someone doesn't want you at a thing, they won't invite you. They'll find some excuse if it is expected.

And if it was a pity invite? Go and assume you are wanted. If it is the rare pity invite, going and assuming you are wanted and acting like it will generally have a better net outcome in your life than not going or going and worrying the whole time about whether you are or aren't wanted there.