How do you say "to break-up (a romantic relationship)" in Japanese?

Question:

What is the word for this? Also, "to have feelings for someone (romantically)" and "to go on a date." Thanks!

Answer:

It's not time for me to get serious:
mada maji-ni naritakunai.
まだまじになりたくない。


I'm not good for you:
Atashi-wa anata ni fusawashikunai wa. (girl < boy)
Boku wa kimi ni fusawashikunai yo (boy < girl)


Forget about me:
Atashi no koto wasurete (girl < boy)
Boku no koto wasurete (boy < girl)


It's over:
Mo owari dane
Mo owari da


I can't see you anymore:
Mo aenai
Mo aenai yo


I don't love you anymore:
Mo suki janai.


I have another girlfriend/boyfriend:
Hoka ni kareshi ga dekita no.
Hoka ni kanojo ga dekita.


I'm not interested in you anymore:
Mo anata ni kyomi ga nai no
Mo kimi ni kyomi ga nain da.


I DON'T REALLY LOVE YOU ANYMORE SO I'M GOING TO CHANGE MY PHONE NUMBER:
Mo suki janai kara denwa bango kaeru.


I hope you liked the last one (: