Forgetting something like a Memorial Day is the worst!
My husband gave me a fully automatic washing machine for our wedding anniversary this year.
On Independence Day, I'm selling clothes at a flea market.
Some days are so special that you have to write down all your thoughts when they're done. These are special days like holidays and your anniversary.
The reading is a combination of on'yomi for the first two and kun'yomi for the last one. That being said, all of the readings for all of the kanji are the readings you've learned already, so you should be able to read this word too. Just watch out because ひ is rendaku'd into び.