Ask HN: how to decently ditch a job

Longtime user here, you know the drill. Long story short: I took on a project I thought I would like, for a client I've got to be friends with, and which am competent for. 4 weeks later I've barely scratched at it, which is going to cause problems for him (competitive entry deadline) and raise the expense. I am an asshole. Why? I've been moving away from that area of work, I agreed to do it for too little money which I don't need anyway, and the project arrived to me months late and with stuff missing. I should have said no, but I'm not good at that. Mitigating factors: I have had some medical and domestic problems, which are genuine concerens. But they are not big obstacles, more like this project was the obstacle to the momentum I had going to deal with the other issues. The more I felt it was a distraction from ym important goals, the less I wanted to work on it, the less I wanted to work the more time I spent perfecting irrelevant marginal aspects (ie sharpening my tools because I'm gonna start on this any time now...), the longer that has gone one the more embarrassed I felt to pick up the phone and beg off. I am late, the work is not done, I have let someone down, I am largely to blame and have made the situation worse by failing to deal with it. Although it will be hideously unpleasant, I am going to just admit this was what happened rather than cook up an excuse...external problems exist, but the failure to cope is all mine. My question is short: what should I say besides 'sorry'? The obvious answer would be to commit to done and have daily checkins or something, but I already loathe even thinking about this project although that is no fault of the originator, it's because of how it makes me feel about myself. I feel strongly that I should terminate my involvement, for both our sakes. In past tight corners I have gritted my teeth and pulled through, and been mad with myself afterwards for limping over a finish line.