Just look on the bright side, dammit.
Being positive isn't always as easy as it sounds.
I'm generally a positive person who looks on the bright sides of things. I've curated my life to eliminate anxiety inducing situations (as much as a I can!) and really only do things that positively affect me to keen me happy.
But there are still dark times. I still get down, and with all my 'mindfulness' I practice it still works its way through.
Today, I'm feeling it.
All I want to do is curl up in bed with my cat and feel sorry for myself (well I'm kinda of doing this now as I'm writing this). But instead, I'm writing this, with the purpose to help bring myself out of it.
It's starting to work, I am feeling not a sad as I was 20 minutes ago. But there's a lesson in this.
No matter how happy you can be, things are still going to get you down. It's how you bring yourself back out of it.
There's not a one-way-fits-all solution.
For me, it is taking that time out in my own head and breathing mindfully, away from people telling me, snap out of it already, but for you, it might be repeating a mantra to yourself, taking a walk or going for a run, getting creative and doing something that actually makes you happy, like cooking a cake, it might even be opening a bottle of wine, what ever your vice (be it responsible!), take it. You need it. Otherwise getting back into your happy place can be even harder to find each and every time.