I was recently with one for 3 yrs.

Sun opposite Jupiter- huge ego! plus venus and mercury in the sign. The show was ALL about him. If it weren't for The Vid we would probably only have lasted 6 months.

This guy is never wrong, knows everything and is constantly cross examining you. (Big time lawyer). I think he liked the idea of me more than he liked me myself. Has a terrible time listening. I used to say, "is it my turn to have the talking stick now?" I also have a lot of water, and when Aries moon constantly tells Pisces moon pluto, "I know you feel XYZ..." Whut? You're trying to tell me how I feel too?

Dragged his feet about commitment and it was of course all my fault. I could go on and on.

It was my dog who ended it.
I would sleep on the floor beneath a window sometimes when my back hurt. Nothing unusual. Picture Sagg bumbling around in the dark bitching at me to get off the floor and to the bed (where 'normal people sleep'). Steps his whole weight on my dog under the blanket in the middle of the night and gets bit. Never wants to see dog again. Oh well. The relationship probably would have dragged on into eternity because (wait for it) Sagg loves drama!! These guys are never done. Ever.

Just the men in my experience.
I have several close women Sagg friends and it seems like they handle the energy better.

my son is a sagittarius with venus in scorpio libra mars.  He has co dependency and also he is a mommas boy.  However he hates lying, and he's truthful and philosophical. as for him dating, i would say, he's more attracted to fire suns with water placements. He does get bored easily and is more an intellectual. He does have aries moon, so thats why, double fire, so its natural for him to gravitate to fire suns, its usually leos, with cancer placements or a libra with sagittarius placements. so the occasional libra because he has libra. how do they break up? maybe he just fades away from them, ghosting. or block them or just dont want to see them again. Cut them off. It might be scorpio venus that is doing that. Since that is the romantic placement. Maybe its different for a sagittarius venus.

edit - does he feel bad? i dont know his romantic life but if he doesn't like them or feels that they aren't good for his future, he just will be blocking/cold turkey out of their life. he also has to feel "safe" with them too. Or he will block/ghost.  but weirdly i agree with this if i dont like someone to be in my life, however, ive never had to ghost or block because i dont jump into relationships easily. I have virgo so im discerning. But i am also venus 12th house so if i fall in love its hard for me to get out. and i can't ghost. i wont be able to ghost or block because i want to make it work and stick with it to my own masochism.