Ask HN: Calendar/event manager that doesn't suck?

I want to create events with a time and date, assign participants and automatically notify them via e-mail (or SMS) a day before. I don't want them to have to download any app or create an user account. And it should work with any kind of e-mail (Gmail, Outlook, custom domain). I would manually manage the name, e-mail and phone number of each person. It would be acceptable, though, for the user to create an account if he wants to check the full calendar with the e-mail he was invited. Just not for the notification and confirmation stuff.

So far I tried:

- Outlook.com: slow, heavy cache problems, events failing to be created, most e-mail notifications don't get delivered (maybe they need to be in my contact list or have exchanged e-mails with me? some kind of anti-spam?), if Gmail users click on Yes/No/Maybe I get "550 Requested action not taken: mailbox unavailable". Tried both with a custom domain and a new @outlook.com account. I couldn't believe how shitty this thing is.

- Zoho: terrible UI, and I couldn't even get the confirmation e-mail delivered. It doesn't even hit my Gmail spam folder. How can I trust it to deliver notifications?

- Gmail: Like Outlook, user needs a Google Account to be able to reply Yes/No/Maybe, or to view the events.

- Trello: Doesn't work for this use case.

Any suggestions? If I need to self-host this thing in 2016 I might give up on the internet.