I had cold emailed an organization a couple of months ago in May to ask for an internship, and while they did not have openings then, they did contact me this February about an internship offering, and how to apply. It is my dream internship, and I botched it by not sending an application. Their initial email was sent over a month ago. It's not that I forgot, but I have not been in a good place mentally and could not, although I tried, finish the job application form and writing samples.
How should I frame the apology? Should I say I had a medical/technical/family issue? I really want to try for an internship there, I'm better now and I'm sure I won't mess up again.