How do you know if your relationship is in trouble?

If you study Communication, I am sure you are familiar with all the theories about relationships, good listening skills, how to be an effective communicator, blah blah blah blah. However, I have found that if you study Communication, you can learn good techniques on how to be more analitical with your personal relationships. Knowing how to read non-verbal cues can be very useful to maintain friendships, work relations and romances. Yes, romances. As woman, I really believe that any relationship should begin with having a healthy communication. But what about if, you are having good physical contact and social life with your partner when suddenly you start noticing some of the following signals:

1. Less vocal expressivenes
2. Less smiling
3. Interactions don't flow easily
4. Increase physical distance
5. Increase in time interactions
6. Fewer intimate terms
7. Interactions are more impersonal (i.e. How is the weather?)
8. Fewer references to the future
9. Less personal languaje
10. More conflict


Do you think is it easier for women than men to react to these cues? Have you experience a situation in which you gave your best effort in a relationship that, at the end, ended up being just yours?

Reference: Interpesonal Communication. Sixth Edition. Beebe, S., Beebe, J., and Redmond, M. 2008. Pearson. New York