I take valerian, to help me sleep. As and when, not daily. It's way better than sleeping tablets, for me, and not habit forming. Takes the edge off anxiety too, again, I use it as and when. Doesn't make me massively drowsy, either, but it's worth trying it out on a night when you don't have work or driving the next day, just in case it works differently for you. I also use ginseng, for a few weeks at a time, when I'm feeling less energetic or lethargic: seems to work for me, but it takes a few weeks to properly kick in. Research them, if you're interested: you could be on other medication that interferes with them, etc, or have a medical condition which might influence your usage.
The rest of it, for me, is all about 'self-talk' and 'image management'. If you know spilling your guts will make you look and feel weak afterwards: don't do it. Make sure other people see the 'you' you want them to see. If you don't tell people what goes on in your head, they'll never know. And, as for self-talk: when I'm feeling low, instead of over-thinking it, I work out why. Usually, for me, it's not depression I'm feeling, but tiredness. Or if I'm feeling fat, or stupid, or too ugly to leave the house, I give myself a quick talking to. I tell myself that I'm not that fat, nobody cares, I'm not so ugly, or so dumb, etc. I try to nip it in the bud rather than dwell on things or allow myself to start 'looking' for reasons to hate on myself.
I also meditate. Not chanting, or visualising, or using apps or any of that bollocks, but proper 'not-thinking' meditation. Just sit, quietly, for five minutes, and try not to think about anything. Nothing at all. It's only five minutes, it won't interfere with your life, taking five minutes for yourself.
Focus on breathing in, and breathing out, slowly, and deeply, and that's it. Set an alarm on your phone, and just practise it, every day. It's hard work in the beginning, and at first you'll notice that your head is crammed with shit and you just can't stop thinking all kinds of bollocks, but, keep trying, and eventually you'll get to the stage when you'll be able to do it anytime, anywhere, and it's useful to be able to put your head into that 'empty' place. Anger, fear, guilt, stress, let it go. Try it. It's great. Works for me, at least.
Hope you find a solution in some of that x