Hmmmm.... well you certainly don't want to act like I did after my last really bad break-up (decades ago).

Though I admit to some good memories of even that lost time.
From my experience with stress in general, I always advise people to back off caffeine and other stimulants, if that's part of their life. Your internal system is probably producing all the excess energy you need just now.
Work out as much as you can. It's good for your mood overall, gets you out of the house and of course does your body actual good (presuming you do it intelligently).
If you've never done meditation, start. Even if it's just sitting in a chair with the lights out and some soft music on while you take deep breaths and repeat some chosen phrase (the old stand-by "OM" is always good). You may find yourself getting emotional if you're new to this - that's a GOOD thing. It means you're letting go of things you've been wasting energy trying to tamp down. Let it out and you'll get past it.
Don't worry about the crap that drifts into your mind. It will. If it helps, replace the spaces with positive words: "abundance", "health", "tranquility". (There's actually some experimental evidence that repeated words have a real influence.)
Be good to yourself. Even spoil yourself somehow.
Be careful - you're probably very fragile and vulnerable right now. Don't make big decisions and be cautious about new acquaintances (though you might need some just now).
If you've got a network of friends, value them. You'll never need them more. And you'll never be more grateful for them, years later.
Enjoy the weird blessings of grief. I remember looking out at the skyline of Paris at night and realizing how exquisitely beautiful it was, seen through my energized state.
Keep a journal (if you don't already).
Look at big things: the sky, the sea. Even the enormity in small bits of nature - an hour in a good garden can work wonders.
To paraphrase Kahlil Gibran*, sorrow carves a bowl in our being that we then may fill with joy. This too is part of making you who you are.
*
Original Gibran quote quote:
The deeper that sorrow carves into your being the more joy you can contain. Is not the cup that holds your wine the very cup that was burned in the potter's oven?