Justin Herbert, Jaxson Dart's Relationships Won't Make It, Astrologer Claims

Justin Herbert and Jaxson Dart might as well break up with their girlfriends now ... because a famed astrologist says their relationships aren't written in the stars.

Richard James -- host of the "StarCast Weekly" show -- starts out by breaking down the Los Angeles Chargers star QB's relationship with his pop star better half, Madison Beer ... which Richard says is unlikely to work out because they're both Pisces.

Plus, James isn't sure the two are sexually compatible ... arguing that because Herbo's Mars is in Aries, he's more sexually spontaneous ... while Madison might be a bit freakier but ultimately looking for something more long-term.

Basically, RJ believes the Bolts QB's relationship feels more like a strike of lightning to him ... fast, furious, and gone before you know it.

As for Dart -- who is dating model Marissa Ayers -- James says the Giants' QB is attracted to her confidence ... but communication is key here, and the stars dictate they have a giant issue there.

Both the Chargers and Giants are out of the playoffs ... so, they'll have to wait until next year to win it all ... and wait until their next relationship to find happily ever after, if James is right.

Richard James has a weekly astrology show called "StarCast Weekly" where he goes through all the signs and tells people what they can expect for the week ahead on the streamer Gaia.