I'm sorry Golu, she doesn't love you. She's just happy to have you there doing all that stuff for her. It doesn't matter how much you do for her, she isn't going to start having romantic feelings for you.
I suggest you stop doing all these things for her and focus your attentions elsewhere.
Also, when you do get a girlfriend, DON'T do her work for her. Sure, teach a girlfriend things she doesn't understand, but don't do the work! You may see it as a romantic gesture, but the reality is that she's missing out on learning. Your deeds are simply teaching a girl to be a lazy cheater.
Never regret anything that has happened in your life. It cannot be changed, forgotten or undone. So, take it as a lesson learned and move on.