Gen X Americans are caught in the middle —supporting aging parents and adult children alike. And while many have built up home equity, a lack of time is pushing them to swap square footage for a better quality of life. Roughly one in six Americans falls into this sandwich generation, according to a  Realtor.com® survey . Of those, 16% are Gen X . Jay Ramsden, 57, of  Boston  is a member of the generation. Known as the “ Empty Nest Life Coach ,” Ramsden assists his two twentysomething kids with