Help! I need a wardrobe makeover!

This day has been quite the stressful one and it is all because I'm trying to get myself organized for London. Before I go through the stress of packing a year's worth of clothes and belongings into two suitcases, I need unpack my year's worth of clothes and belongings from New York City. I truly believe this unpacking is the more difficult of the two tasks. The greatest task of all...organizing and fitting all of my clothes into a single, average-sized walk-in closet. Sounds easy, right? WRONG! I know I have been complaining about all of the crap and clothes I own...but today has been the true realization. I wish I could just purge everything and restart with a completely fresh wardrobe. Somehow over time I have collected a ridiculous, disgusting amount of clothing. I blame it fully on stores like Forever 21, H&M, Marshalls and TJ Maxx. I would say about 60% of my wardrobe comes from these stores. The great low prices and huge variety is the problem. It is so easy to buy a lot of clothes for a decent price...hence the pile up of more and more articles of clothing and now the jam packed closet. Many of you are probably thinking, "you just need to get tough and throw things out or give them away." Believe me, I have gotten rid of a lot and have been pretty ruthless about it. I have two huge 40 gallon trash bags full of clothes to bring to goodwill. Here is one of the trash bags and here is a pile of purged clothing from the other trash bag.
So what now? I am still left with a closet filled to the brim with clothing. And what do you do with clothes that have sentimental meaning? Like that t-shirt you got at your first concert? Or the clothes that you know you can fix...like the good pair of Lucky Jeans (handed down from my mom) that fit perfectly but are missing a button. The funny thing is, they are not really in style anymore. Ugh so why are they in my closet!!! I may or may not have some hoarding tendencies. HELP!

My dream would be to have a OCD organized, monochromatic walk-in closet that felt like I was walking into a small boutique, ready to pick out my outfit for the day. These would be some of my fantasy closets.

The funny part is I can only bring about 1/10 of my wardrobe to London. The refreshing part is that it will teach me to live simply and to work with the best of the best from my wardrobe. I know this sounds crazy, but I am sick of having all these clothes. I just want a basic set of 20 classic pieces to mix and match that fit perfectly and I love. Then I could OCD organize those 20 pieces and make my life so much simpler. Only in a dream world I suppose. Maybe that dream world will be London. Time for a fresh start to my wardrobe. London is calling!