As a guy in his 30s, I have one observation. Ever since I first met her and started having sex with her, my wife has had a very emotional response to sex. It is not uncommon for her to cry (not in sadness) after sex, especially when she has had an orgasm. She attributes it to a much stronger, inate emotional attachment that women have to sex compared with what men typically experience. Based on what you have written, it sounds like you take sex very seriously, and I'm sure that it is a commitment that you do not take lightly. Considering you have only had two partners, this is totally understandable and commendable.
I wonder if the guy you met this weekend has any idea how much you have thought about this and how much it means to you. I have a son, and I have promised my wife to teach him to not take sex lightly, and, although he may see it as physical, women he meets likely will not, yet they may not give a true indication of what they are feeling inside. Therefore, it will be up to him to be considerate of the strong feelings and emotions that his partner may be dealing with.
All that being said, don't beat yourself up over your decisions or think less of yourself as a result. As everyone has said, you are single, took precautions, and made a voluntary choice involving your own body. There is nothing wrong or dirty about enjoying sex...it really is fantastic. The trick is balancing the strong physical desire with the equally strong emotional response.
I'm sorry if I'm rambling or reading too much into your posts, but I just thought you may want a guy's input.
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