I found this interview fascinating, because it resonates so much with who I was 5 years ago. (You don't have to pay to read it - just watch a short ad.) The book author is a single woman who used to be promiscuous, but who's now committed to not having sex until marriage, and she describes why she thinks it deepens her relationships with people. A few excerpts that resonate with me:

the impression I got growing up was that men come and go, and you can't expect one to stay and value you, and you certainly can't expect one to marry you if you don't have sex with him. I really wanted to get married, and I believed that the only way a man would marry me was if I had sex with him.
I think the "Cinderella" type fairytales are the most destructive influence possible on a young girl. Your prince won't arrive until you're someone who values herself, and it's hard to both value yourself and give your body away freely.
I delayed full sex in part because I tended toward depression and feared that if I had sex with a man who didn't stay with me, I would fall into deeper depression. Which of course is what wound up happening. I got into my 20s, past the age when most people got married, and my dating life had not resulted in marriage. So I became cynical. I thought, "If I'm not able to get what I really want, which is marriage, I should get whatever pleasure I can." And so I fell into this vicious cycle: being lonely and depressed, having low self-image, having sex, thinking it would make me feel attractive and better about myself, and the man would leave, and I would feel more depressed and lonely.
I suppose some women can have sex without attachment, like some men... but is that really what we want to strive for?
Chastity isn't just about avoiding sex or sexual fantasy; it's about being open to all the blessings that others have to offer and not trying to fit people into pigeonholes. I have all these things I've been hoping a boyfriend would do with me -- holding my hand in public and going to the Metropolitan Museum of Art. I have a five-page mental list, and some he'll want to do with me and some may not be his style. He might not be the kind of man to hold my hand in public. He may express his affection in other ways. In that sense, it can be just as objectifying to picture [how he would behave at the wedding].
Women objectify men just as much as men objectify women, and it does the same degree of damage, because I've run across a lot of men who are afraid to be themselves because they think they won't match up to Hugh Grant in "Notting Hill" or Richard Gere in "Pretty Woman."
Instead of following the pop-culture prescription, to single-mindedly pursue a man who's going to make you happy, I am suggesting women should be singular and concentrate on being the best people they can be and displaying grace as individuals and as women. In doing that they will become more giving, more appreciative of everyone around them, so not only will they be better able to have meaningful friendships and relationships, but they will also be able to enjoy this time they have as singular women.
When I stopped having meaningless sex, I stopped objectifying myself.
If you're giving your entire body to a person without giving yourself emotionally, you're creating a dichotomy. You're setting yourself up to compartmentalize all your relationships into transactions.
Sex without attachment tends to involve a lot of gameplaying and manipulation, because without attachment, it's hard to have trust. This sort of mentality spills over into the rest of one's life, and I found myself thinking "what can you do for me?" rather than "what do I bring to the table?" If the person you've given your body to might just walk out the door at any moment, you learn to take what you can quickly and by whatever means necessary. Yes, friends-with-benefits is possible, but I've found a catch-22: if the sex is really good, it's hard to stay detached, and if the sex isn't that good, why bother anyway? Might as well masturbate.
What I'm trying to say is that whatever you're doing in your sex life is going to impact your ability to give emotionally in other areas.
Not only to others, but to yourself.
I was, as you say, focused on pleasing men, but I was also very narcissistic -- I had simply tied sex up with my self-image and thought, "If a man is not going to necessarily stay with me, then at least he can show me I am valuable in some sense by having sex with me."

Again, this was my thought process, five years ago, and I'm eternally grateful I found a way out.