I wouldn't sell just yet. It all depends on your timeframe. It's still paying out, and if you're doing dividend reinvestment, then you're automatically buying shares at this lower price. It's still generating income for you. You don't have to reinvest dividends. You can use them to buy index funds or another stock.
This is how people lose money in the market. They panic and sell low. Stocks are most volatile in the first year. The longer you own it, the less those dips matter. I bought SNH a few years ago at around $21.50. Thanks to div. reinvestment, I'm not down by much. I'm planning to hold onto it for the long haul. Everyone's financial sitch is different, but if you're able to hold, then do so. I mean, baby boomers are just starting to retire, so retirement homes will still be needed in the future.
More importantly, nobody knows what's going to happen in the future. Maybe it keeps dropping then eventually goes back up in a few weeks or months or years, or maybe it doesn't. I own TGT, and that plummeted last year, but finally, it's making a recovery.