I’m a solo traveler from time-to-time as well. I’m SO glad you didn’t let your single status prevent you from an amazing trip! I had a marvelous time in Paris this past August and visited the spectacular Christian Dior exhibit (story here) all by myself.
London is my favorite non-US city and is very solo traveler friendly, too! I look forward to hearing about your adventures. I need to post a lot more about London, but I do have a few London pointers for my favorite walk and art spots. Soon to be added: my favorite fashion stops and a story on my favorite Covent Garden shops/experiences!