I think a lot about attachment and just wanted to share my thoughts.
Attachment is always generated by need for one of the five A's (acceptance, appreciation, affection, attention, or allowing).
When we are attached to something we believe that we need it in order to be happy. We think our happiness depends on it so we fear losing it (because we think we will no longer be happy if we lose it).
The ego looks for things to identify with (i.e., to become attached to). Desire for physical comfort, emotional comfort, financial security, etc. can never be fulfilled. Once you have the object of your deisre you will crave more and more of it. Once you obtain it you often have trouble enjoying it because you begin to worry about losing it. In this way, desire produces attachment.
What we don't realize is that we don't need anyone or anything in order to be happy. All you need to be happy is within you. It is futile to seek happiness from external sources -- external happiness is temporary.
To overcome attachement focus on giving to others what it is you desire. If you desire affection be affectionate towards others. If you desire attention give others your undivided attention. If you desire acceptance give to others your unconditional, nonjudgmental acceptance. If you want appreciation then show your appreciation to others. If you want allowing then allow others to pursue their dreams without passing judgment on them.