Express your concerns about the relationship in non threatening ways-definitely easier said than done. Whether you speak softly or loudly, accusing or accetping responsibillity for part of what does not seem right to you, your partner knows that you are unhappy about something and it has to do in part with his/her behavior or attitude. Thus, no matter how you frame it, your concerns will most likely be interpreted in some way as an attack-especailly if your partner believes that she/he has been working really hard to meet your needs.
That said, there are some steps you can take that will enhance the chances of reaching your partner:
1) Wait until you have examined your own frustration or anger about the particular issue before approaching your partner and you have taken time to calm yourself down.
2) Be prepared for a defensive response no matter how you present your concerns.
3) Be prepared to listen to your partner's explanations without getting defensive yourself.
4) Start out by saying that you know it might be hard for your partner to hear what you are saying and you would like him/her to at least hear you out before responding
5) Try to be concise and to the point. The longer you talk the harder it is for your partner to listen.
6) Try to give them the benefit of the doubt.
7) If you are asking for some change, try to be specific about what it is that she/he could do that would make you feel more connected or loved
8) If your partner does become defensive, ask that she/he take a day to think about what you have presented and than talk about it the following day when you are both calm.