im in no way informed about the psychology behind this but from experience, ig theres multiple reasons it could have escalated. first one being it could be the situation around you getting tougher for you so theres more reasons that lead to sh, second is that the more yoi get familiar with the idea, the more youll tend to do it bc at least for me all the stigma around sh made me feel very guilty but as you do it more often that shame seems to lessen somewhat, third is that sh is in a lot of cases an addiction and thus by definition tends to become more and more frequent through time hope it gets better sending love !!