I have noticed this tendency in women to not say what we want. Fear of being too needy, too bossy, too demanding, keeps us quiet about what we really desire, and from addressing the relationships that don't fulfill those desires.
What is it to be needy? To need to be treated in a certain way; to need to be loved; to need to be respected; to need to be fulfilled - any of those sound like bad things to you? I'd much rather be openly needy than quietly unhappy.
Needy doesn't have to be synonymous with desperate. Desperate happens when you spend months - or years - denying what you really want, until your reduced to moments of insanity because denial wasn't working out for you anymore. You get labelled as "desperate" when you completely blindside another person, because you were quiet for so long that they literally had no idea you felt that way. Desperate is the way you feel when you live with stifled desire, and the voice inside your head that tells you what the other person should be doing. In reality, you should be doing something; you should be saying something. Other people cannot read your mind - you need to be willing to speak it.
What is bossy? We're not kids on a playground trying to get everyone to unanimously agree that we're the leader, and to just shut up and follow the rules. We're adults looking to be create the lives we want to live. If we hope to live those lives with other people, we have to be willing to have discussions, we have to be willing to comprise. That starts with one phrase: "I want ____, ____, and ____" followed by "do you want the same things?", or "what is it that you want?". It is that simple. Sometimes you've got to be a little brave to facilitate honest conversation.
The same is true for demanding. To know what you want in a relationship (whatever form that relationship takes), is not being demanding - it is being conscious. When we don't know what we want, or when we're unwilling to openly ask for it, we end up settling. As we're all reasonable people (right?!), we're not going to make ridiculous demands of another person, ever. What we are going to do is say: "I want ____ in order to feel happy, fulfilled, and loved; how can we make that happen in a relationship that works for you too?"
None of the above scenarios are unreasonable or scary. We make them scary when we play out the conversations in our head, and imagine all the ridiculous, and absolute worst case scenario answers that the other person could give. Be brave enough to ask the questions, and then allow them to answer for themselves. Chances are if you love them it's for good reason. Or maybe it's not - maybe they really suck. Wouldn't you like to walk away before you waste years in a relationship that would never fulfill you anyway? Wouldn't you like to know that you did everything you could, and that you have nothing to regret?
Losing other people is painful, but losing yourself is a death sentence. Be brave; be honest with yourself and the people you love (or want to love). Vulnerability results in growth, I promise.