When you express your needs and opinions in I-Messages* and do get resistance, you will almost always defeat your purpose if you continue to repeat your self-disclosure. Reasserting your need or opinion in the face of resistance usually comes across as aggressive and insensitive. It puts others even more on the defensive and stiffens their negative reactions to what you are trying to communicate. 
What they hear from you is: “This is what I want (or think), regardless of how you feel about it.” To increase the chances that the other person will hear your I-Message, you need to listen and acknowledge her or his upset feelings.
A willingness to be sensitive to the other’s feelings and concerns is what separates assertive from aggressive behavior. Even though you send a very clear I-Message, if you fail to take into account the other’s negative feelings, you are in effect saying: “I want to be heard or get my needs met no matter what!”
Therefore, as soon as you become aware of the other’s resistance, you should “shift gears.” After sending your I-Message you shift to listening to the other’s feelings; from initiating to responding. You now want to be sensitive to the other’s feelings.
You want to show concern for—and a genuine desire to understand the needs of—the other person. S/he now hears an attitude like this from you: “Here’s what I value. But I’m willing to stop and listen to you, because I value you and respect how you feel.”
This temporary shift to the other person’s concern sets up a conciliatory atmosphere. It communicates your sensitivity to (and interest in) her or him. It lets others know you’re not out to get your needs met at their expense. Shifting gears does not mean you abandon your needs or your convictions.
It does mean you recognize that dealing with the other’s resistance is an integral and indispensable step in getting your own needs met, that you value the other person and are interested in her or his feelings too. One shifting of gears (to listening) is often sufficient to help the other person vent her or his negative feelings. At other times you may find it necessary to shift back and forth from disclosing to listening several times.
*The I-Message was created by Dr. Thomas Gordon, author of several books, including L.E.T. and P.E.T.