I overthink things too and 'analysis can lead to paralysis' is my motto to avoid. I too have to focus on the moment as much as possible and TRY desperately not to think too much about any personal issue, let the feelings come and let the thoughts pass. Sometimes I can succeed but it has been my nature for a really long time to overcome. I visualize a river now, put the thoughts on some leaves, and not acting, just let them go, letting them just float by to get me into the next moment if they become overwhelming. Otherwise, it's easy to begin to ruminate on the thoughts, which are not fact, just thoughts, and use this as a checking mechanism too so as not to give them much credence. In that moment, I can turn my mind to the task at hand and not get so caught up, but it is a constant, sometimes stressful, and anxiety provoking struggle.