I have found in the past that anything that directly affects my overall well-being (making me anxious, depressed or feel bad about myself), seems to cause the rumination to start up.
I am not experiencing it during the lock-down (luckily) but it is because I have found some things that really work for me.
First - I have become very attuned to my emotions and can usually sense VERY early if something is triggering me, or if I am not feeling quite up to par. I don't wait to see if it gets worse - I immediately do one or more of the following:
1) I check to see what I am watching/reading - 9 times out of 10 triggers come from media consumption. I will take a break from social media, reduce TV watching and immediately seek an uplifting book to listen to or read. I have an Audible membership and I love listening to a funny or inspirational story while working in my yard or around the house, taking a walk or some other physical activity. It helps me change my mood and if I combine it with physical activity I get a sense of accomplishment and neuro-chemicals to boot!
2) I start looking for ways to build myself up. I have actually had a really enjoyable time during the lockdown, even as I worry for the impact on those I love and the world in general. I have a long background in marketing and events. A lot of the projects I was working on were cancelled, moved or became virtual. I threw myself into learning everything I could about taking my events virtual and learning new software and skills. I played with creating marketing videos - something I'd always found interesting but never had time to pursue.
3) I start helping others. I took everything I was learning and offered to put it to use helping local businesses and non-profits fighting for survival. I've created ads, planned marketing, helped organize a community wide online storefront where people could buy from local businesses and the money went back to the business, etc. It kept me busy, energized and I love helping people. I enjoy knowing I made someone feel a little less alone during a scary time. That helps me feel better about myself and the world. Which, in turn, reduces my anxiety and depression.
4) I gave myself permission to play some. I did projects around the house I'd wanted to but always felt like work or family were more important. Every time I look at my newly cleaned and organized garage or my sanded and whitewashed bathroom cabinets, I feel a sense of accomplishment and pleasure. I did that! And it is GOOD. That makes me feel good about myself and when I feel good about myself I don't ruminate much. Instead I find myself thinking how lucky my husband is to have me! (LOL!!)
Also, I make sure I am eating well and getting regular sleep. A tired or hungry Thrive is not a good Thrive - she usually gets cranky and nothing good happens after that, haha.
Anyway - I hope any of this helps. It isn't easy ever - especially right now - so be kind to yourself. And whenever you need a pick me up, reach out here or on PM. We are all here for one another!