What strategies have you found for either dealing with the negative feelings, or addressing the cause of loneliness, and have they worked?

On one side, a feeling of loneliness is a signal that in my life I should socialize and connect more.
Other times though, decisions and actions taken under that emotion turned up to be pretty bad: it would have been better to just be and feel alone.
I have thus filled up my week but have left slots of time to be alone, and I know that any feeling of loneliness that I get is just a withdrawal symptom.
I've filled my social life with dancing classes, founding a local go club, joined a teaching class and time to go out with my generic friends. On the other side, when I still feel alone I just take some minutes to sit quietly and imagine being in a pleasant social or sexual situation, trying to focusing on every detail. This is usually more than enough to clean me from any negative state of mind.