Why do women reject me always?

All of my friends are in serious relationships and I always meet them with a sinking feeling because I know I will be depressed by the end of every outing. They don’t say or do anything to make me feel lonely, but I can’t help feeling as if there is something wrong with me because I have never managed to get into a relationship with any girl. I have tried asking a lot of them out on dates, but it never happens and every rejection only makes me feel worse. How do I gain the confidence my friends have? What if there is something wrong with me?
Maybe you can try changing your perspective and focus on the fact that you have great friends to spend time with. Relationships of any kind cannot be forced and can only happen when two people decide that they would like to spend more time with each other. Asking people out is great, but it’s also okay to just chat with new people now and again, and get to know them better instead of figuring out whether this is a date that will culminate in something romantic. You just haven’t met someone who understands you, and that will happen only when you go out more and ask your friends to introduce you to people beyond your immediate circle. Don’t worry too much about this because confidence comes with time and acceptance of who you are.

I have been asking this girl out on a date for two months and she keeps saying she will think about it, then refuses. If I don’t message her, she flirts with me online. Is she just an attention seeker? Should I simply stop communicating?
She clearly wants your attention, but where you draw the line is up to you. If you have asked her out multiple times and she isn’t ready to meet you in person, you can choose to give her more time until she is comfortable, or assume she isn’t genuinely interested.