gemini,First of all, this "message" from the astrologer is some spam that has been circulating for awhile. The give away to this fraud is: "These planets will approach the position in which they were in at the precise moment of your birth( (Venus:57°18'...". No astrologer would say this: they would include the sign and a number between 0 and 30 to indicate the degree.
As to the rest of your question. Since you have an unaspected (strong energy) Venus (relationships) conjunct your Descendant (relationships), you do not feel "connected in" with relationships. As a result, you are INTENSELY involved in relationships, as you work to try to "connect in" with relationship energy. The result is anyone whose energy aspects your Venus becomes a "potential relationship". The challenge is most of these "relationships" were not relationships to begin with.
It is not a matter of "judging you" to say that in going out with young people, who are just beginning to discover who they are and barely beginning to reach out to others to BEGIN to develop relationships, the chances of "getting dumped" is VERY high. Instead, I suggest you go out with people your age or older, who are already familiar with relationships, who share similar interests and who you can have long-term possibilities. Learn more about the astrology of YOU and,once you understand this astrology use your astrological knowledge to begin interpreting relationship charts (synastries). This will help you find the relationships where you DEEPLY connect in, as opposed to simply have a vague relationship with.
As to this person, he has Uranus (friends, also impulse) conjunct (energy is combined with) Venus (relationships), so he may tend to get into (and out of) relationships impulsively. Given his age this is VERY likely. An older, more mature version of him may not be as likely to "love 'em and leave 'em".
Suggesting looking for more mature people,
Tim