Deities in Buddhism?

At our center we do a Red Tara practice two times a month. Tara is a feminine deity in Buddhism, but what does that mean, exactly? The answer is complex, but this Wikipedia article is a good start. Some Buddhists think of Tara as an actual separately-existing deity, or Goddess, that can be prayed to in much the same way some Catholics pray to Mary. Indeed, Tara is known as the "Mother of all Buddhas." On the other hand, many Buddhists view Tara and other deities as emanations of ourselves. By praying to and visualizing Tara, we really are visualizing those good qualities in ourselves we wish to bring forward. At first this may seem narcissistic. Worshiping oneself seems like a bad idea, after all. However, we are not worshipping ourself in the self-absorbed narcissistic sense, we are honoring that part of ourselves which is best, and which we wish to cultivate. Also, by giving our good qualities an anthropomorphic embodiment, we can honor those same qualities in all sentient beings by praying to, and visualizing this embodiment. This reminds me of a poem I wrote once while under the influence of a mind-altering substance. (Those days are gone now.)

"Hi my names Happy. I am a traveler of time and entity."

That is, one can think of happiness as an entity which travels through time and jumps from person to person, in much the same way the body of good qualties can be thought of as a deity who manifests at different times in different people.