A patient recently told me she felt unloved. She blamed her husband for not doing enough to demonstrate his love for her and said she was having doubts about whether or not to stay in the marriage. I asked her how long she'd been feeling this way. "Not long," she told me. "Maybe a week." I asked her what had changed about her husband's behavior over the past week. She was not able to identify a single thing her husband was doing differently than he'd been doing when she did feel loved.
The problem, I concluded, was that she was accepting her feelings as fact. This is called emotional reasoning and it goes something like this: "I feel unloved; therefore, I must not be getting enough love from my husband." Another example: "I feel anxious and worried; therefore, something must be wrong." Yet another example: "I feel sad/depressed; therefore, something must be wrong with or missing in my life."
Now any of these statements might be true. However, feeling a particular way is not enough evidence for us to draw any conclusions one way or another. We need more information.
The point is this: Feelings are not facts. Emotions are a valuable source of information but they should never be the only source of information. This is particularly true with those emotions that have been problematic for us in the past.
Here's a personal example. I used to be very insecure and jealous in romantic relationships. I became upset when my significant other talked to or even talked about other females. It didn't take long before this caused problems for me. I often over-reacted to benign situations. My suspicions and accusations pushed those I cared about away. I knew I had to make some changes.
I started to interpret feelings of jealousy as a sign (or a "red flag" of sorts) that I need to take a step back or remove myself from a situation for a few moments. First, I would acknowledge my feelings of insecurity. Then I would attempt to determine whether or not they had any basis in reality. Sometimes that meant calling a trusted friend or family member to explain the situation and get their point of view. If I determined that I was over-reacting (because of my own insecurities) I did what I needed to do to cope with my emotions without taking my feelings out on my significant other. If I decided that my significant other had, in fact, done something to warrant my jealousy I worked to identify an appropriate way to address the issue with him.
This took a lot of practice but over time it became second nature. Eventually I even started to feel more secure in my relationships.
Anyway, the moral of the story is that accepting feelings as facts can create a lot of problems. To really make good decisions you need a good balance of reason and emotion. In other words, when your head and your heart are in agreement you know you are on the right path.