When it comes to saying no, keep in mind is that a girl who never learns to say no is a girl who will have the hardest time finding love. This is because of how much time she wastes trying to be who she thinks men want her to be. As a result she settles for lust when she longs for love. Hold out for love, and imagine your future spouse out there going through the same struggles. He should have the strength to wait for you, and you should have the strength to wait for him. All we must do is pray, have courage, and act.
A girl I know came home crying after a date, and her mom asked her what was wrong. She said that as soon as she got into the guy's car, he started to make sexual jokes, and she let him know that she practiced chastity. He said, "That's cool--there's lots of other stuff we can do." (meaning everything short of intercourse.) She gave him a quick explanation of chastity, and how it meant that she respected her body, and that she would not be doing anything with him that she would not want her future spouse to be doing with some other girl. He looked at her and said, "So, you mean I'm not going to get anything?!" She said yes, and he turned the car around and dumped her off at home.
Was it embarrassing? Perhaps. But regret lasts much longer than embarrassment. Instead of giving him what he wanted as a way to keep him interested (while secretly wondering of he really loved her) she stuck to her morals, and tested his love--or the lack thereof. It turned out he was not man enough for her. Game over. This leaves the door open for real love in her life because she wasn't clogging up her love life with guys who only loved pleasure.
Being desperate only harms a girl's chances of finding love because it makes her more naïve. I remember one girl e-mailed me and said, "My stupidity coupled with my effort to be nice to everybody makes it hard to stand up for what I believe in." If you can relate, then it's time to get a backbone. If you don't have a backbone, then you will give more and more of yourself away, and yet you will feel that you have less and less to offer. Before long, many girls end up thinking that sex is the only thing they have to offer guys to gain their interest.
If you're looking for a sense of value, realize that rare things are worth more. Girls (and guys) without standards are easy to find. And they're also easy to get bored with. On the other hand, the more pure you are, the more desirable you become. Sure, at times the standard of purity can bring about times of loneliness. But don't feel too depressed about that. Even the most popular people in the world feel loneliness, and perhaps more than you would ever imagine.
When I first moved to California after college, I hardly knew anyone. Whenever I would feel lonely, I would try to ask myself, "What am I doing for people who are worse off than I am?" It's an excellent way to put things back into perspective, so you can realize how grateful we ought to be. Instead of acting like a victim, you stop moping around, and you build others up.
More important than all this advice, though, is to avoid getting in that situation in the future. You should not be dating a guy that you need to say no to. The guy should guard your purity, not wear it down. Often, a girl will find herself asking her boyfriend time and time again to stop. Her real problem is not learning to say no to him, but looking in her heart to see why she is so desperate for the love of a guy who does not respect her.