If one is constantly getting lost in the rumination despite ordinary attempts at meditation, my recommendation is to use a technique to substantially interfere with the rumination and maybe get it down to a more manageable level so that one could eventually practice with it. In some ways we need to interrupt the rumination and get some distance from it.
This is not tremendously different from what I recommend in general, that is, to start with a technique that forces one to be aware and present, and later on (maybe much later on) laddering up into open awareness practices.
One practice for rumination, and this is an example of a fairly hard core technique, is to use noting (see elsewhere on this site) along with breath counting. This is admittedly a lot to do, but then again we may need a lot to do to interfere with rumination. For the breath counting I count the out-breaths to 12, and then start over at 1.
Why twelve? On the one hand it doesn't really matter. But there is a lot to keep track of in this practice. We're counting, but we then go off and do a note or two, then we go back to the count. It can be hard to stay continuous on the count at times. So, a bit technical and insane, but to make the counting a little bit easier to keep track of, I visualize the 12 points of a clock, and I use that continually rotating directional sense to keep additional track of the number. I do noting on the in-breath, noticing and labeling whatever arises in experience. Typically I will make 1 to 3 notes during that time, just whatever comes up in the moment.
So noting on the in-breath, and counting on the out breath. We combine the mindfulness of noting with maybe the stability of breath counting. By practicing this way one can seriously interrupt the rumination process and get back to a more calm mindful mind.
