I am such a pure guy probably because my family is Catholic, and I am such a realistic person that I just couldn't simply believe in god that easily now (have been skipping weekend churches for months, since my failed chase-for-first-girl), since I believe I can solve the problems individually without someone to depend on. Moreover, to give you a clue about me, a lot of people described me as a fun, and nice (I know right? "Nice guys finish the last", or perhaps last equals forever?)
During the second year of my college studies, I put the best of my effort in trying/studying things about relationship (even tried to read a book about it). I simply hangout with several girls individually. During that period of time, I felt a huge boost of energy in doing so. I was really active and even got one held hands and slept with me (too dumb I didn't make any further moves as both of us were like tipsy/half-drunk)
Until one that really struck me. In beforehand, I used to dye my hair brown because I lost to a guy while getting a girl during the first semester (the guy dyed his hair too, it struck me too but I tried to move on with that eventually).
The real story starts here: Before the second semester ended, I had a huge crush on a girl I met during my friend's birthday party. I basically went all in, flirted/complemented her a lot, hangout/grab food with her several times, studied with her sometime and spent a month getting her.
Then, exam week was approaching, and I literally spent the whole week to plan prepare a piano song (some romantic Chinese movie theme) to confess my love to her.
I don't get why, like everything seemed to flow so smooth during the piano confession, but after eating with her and playing the piano song, she told me she treated me as a friend, and she also tell me to not dye my hair (she knew the story behind why I dye my hair) after this.

For around 3 months after the rejection till now, I refused to dye my hair brown again (pricy, and majorly her request), and I stopped flirting completely. The dating sh**/hope is getting less and less, and it as well correlate to my self-confidence towards girls. Some of my best friends noticed my confidence drops too. Now, I just don't approach girls as easily, and am more worried about failure. And day by day, I feel that I am too old for this sxxt.
I really don't know how to deal with this, and how to become successful again, because I just don't believe in love anymore, since it seems so out of reach, thus here comes the confidence drop. I tried to think that "They would come eventually for me as long as I don't act needy", but I find this really anti-intuitive, and how can you really get them when you don't make moves?
I am so thirsty at the same time that I am sometimes thinking of going to the red light district. (Is this even a good idea?)
Last but not least, I know you all would tell me how "Oh! It's not such a shame because virgins/singles are precious due to their inexperience!" etc, but this would not even help me to proceed. Things like "Oh! You need to move on!" won't solve this as well, because I tried, and realized that the real path to moving on is gaining actual successful experiences (I don't have any, unfortunately/what's wrong).
At the same time, I feel hopeless so please give me some useful advice about girls and confidence.;( I feel that my effort spent did not give me what I wanted exactly. Afterall, I simply couldn't live life with simplicity anymore, even if I did it would be a really short while. Or, should I dye my hair gold instead of brown to get rid of the rejection sh** and to regain my confidence? Like I don't think gold hair fits my personality.