You mentioned "lowering your standards". Maybe really examining what your standards is a good place to start. Instead of "lowering" maybe you have to consider it an "updating/maturing" of your standards.
Lets face it, the more we age, the less we appeal to the young hotees that we grew up pursuing and dreaming about. And as we get older, the glamour and flash becomes less satisfying anyway in a relationship than maybe someone that's interesting and amusing to talk to and be with, genuinely cares about you, shares your outlook, goals, concerns, etc. It becomes more about companionship than having the most impressive person in the room on your arm as you mature.
When I was younger I had relationships with many beautiful and glamorous women. My friends were all shocked when I finally married at 35 someone who wasn't nearly as attractive physically as the ones I'd been with before. But she was absolutely devoted to me, took family extremely seriously, dotes over our kids, has a great sense of humor, strong character and a rare quality of kindness. Even though I never had a relationship last longer than 3 years before and a very active social life - we've just celebrated our 16th anniversary and been through thick and thin together.
But at 35 I changed my standards to reflect less what society told me I should look for in somebody and more what I really thought were the traits I could live with day in and day out. My advise would be to update and make your standards more mature, and then the hardest one: forget your standards. Instead of evaluating everyone you meet as a possible mate against your preconceived standards and needs - just "discover" people. Just try to understand who people really are regardless of who you NEED them to be (tip: most people think of themselves as the opposite of how they would like to appear). Once you really know and understand someone, whether or not you're attracted will take care of itself. Hope this helps.