B"H
Most of Yom Kippur I spent in the Jewish Quarter of Jerusalem's Old City. At the new and super posh AISH HATORAH complex right across the Kotel (Western Wall). Inbetween the prayer service, Rabbi Yaakov Marcus (from the women's seminary NEVE YERUSHALAIM) gave quite interesting classes. Mainly Q & A on Yom Kippur or Judaism as a whole. Interestingly, many questions came from young American Jews concerning "Intermarriage".
Especially the subject of "Intermarriage" seem to raise lots of interest because the worldwide figure of Jewish Intermarriage is rising. Just look at Chelsea Clinton's "husband". According to Halacha they are not married, as there is nothing in Judaism such as a Jew marrying a Gentile unless the Gentile converts to Judaism. Meaning: According to Jewish law, Chelsea Clinton is not married to a Jew because her marriage to the Jew is non - existent.
During the class, some American youngsters in their twenties asked Rabbi Marcus why a Jew cannot marry a Gentile. The Rabbi's response:
A Jew can be related with a Gentile on a Nefesh (desire) level as well as on a Ruach (emotional) level but a Jew has a different Neshama (soul) from the rest of the world and thus can never be a soulmate of a Gentile. An Intermarriage may work but the two souls can never be connected.
In case the Gentile honestly converts to Judaism:
Then he receives a Jewish soul and the two souls may fit together !