I tend to hide away in the bathroom or other secluded area for a bit and vent it out. Sometimes healthily, others not so much. If anyone comes near I always have an excuse pre-planned. But, on my part, at least I'm not bringing others down around me or getting myself caught with my predicament. (And no, I'm not advocating for how I handle things, just sharing my experience.)
Admittedly I only go outside a few times a year now (disabled + chronic pain&fatigue + agoraphobia + etc.), so I don't have to worry about it much anymore. But I sincerely hope the best for those going through something similar.