Ray J -- Ex-GF Threatened Suicide Because Karrueche's in the Picture

Ray J's ex-girlfriend who threatened suicide Wednesday was pushed over the edge after she found out Ray was nuzzling up to the modern day Helen of Troy ... Karrueche Tran.

Cops were called after Princess Love called Ray and threatened to shoot herself. A short time later she called him back and said she would not go through with it.

As we reported ... Ray broke up with Princess Love Tuesday night after a big fight. Now we know where he went afterward.

Ray went to a studio to shoot a New Year's Eve special for BET. Karrueche was also on the show and Ray hung out with her until 4 AM. We got a couple of pics which show they were definitely getting along.

Unclear if there's a relationship, but it's definitely a good start.

Looks like Ray J's doing some damage control ... he posted a pic with Princess Love late Wednesday night with a very poor choice of words in the caption.