Gratitude has been a big one for me. Just simple appreciation of what I DO have, as opposed to thinking about what I lost. Also being glad of the things I can now do without being in the FOG about them.
Exercise is also my first go to for all situations. I train HARD. I do a combination of strength and cardio and can give any bloke a run for their money in the gym

Helps me to feel physically strong and that helps my inner strength to grow. As you said, Sluggo, having physical insecurities thanks to the ex has meant two birds with one stone. I'm in way better shape than when we were together and the only downside really is all my clothes are now too big!
Practising mindfulness. Enough said.
Focusing on long term goals is a good way to get to grips with 'real life' minus a BPD relationship in my case. Feel like a blank slate, having every opportunity the world has to offer at my feet. Both exciting and daunting simultaneously. My mental and emotional health is a long term goal, so I've applied myself to getting the right help and moving things forward. Just one of the steps I've taken has come to fruition today. It's called 'art on prescription'. A referral into an art and creative well being centre. Went to look around today and it is really fantastic. Can't wait to get started.
These are only a few examples, or else it would be a massive reply! I think there is no end to the ways that we can deal with the pain. Everyone must find what works for them. Ultimately, we must feel and accept the pain, yet it doesn't need to take over our every waking minute. There are tons of things we can do that are positive for us, including giving ourselves a break and allowing ourselves to indulge a little in the things that give us comfort and also soothing, which is vitally important.
Love and light x