I was the same before not being able to even complete rare event and and never got far in the other 2 but I did try and keep trying as I am not one to back down. If you go in expecting to lose then losing is more amusing than it is frustrating.
This event thought I actually completed the rare and epic and currently on the last level of legendary which I don’t expect to complete as little red riding hood is quite tough there protecting the other 2 but I will keep trying.
I also put clips out in youtube which has helped other team members out.
I had actually had a 30 minute battle (yes also uploaded) on last level of legendary but my loss help 2 others complete that level so I am happy.
Events are a sort of bonus extras for those who can achieve them and not meant to be easy.
Have fun with it and learn from it.