Maybe jealous isn't the right word.but if your girlfriend is ok sharing you with another girl, you can guarantee she'll expect you to have the same "ok" attitude if she's talking to another guy "friend".
Never go back! And if what broke you tries reaching out to you again, ignore them. A valuable lesson for everyone to know. If they broke you to begin with then he didn't love to fight and be better for both of you.
One of the hardest decisions you'll ever face in life is choosing whether to walk away or try harder. Trying harder is pointless if she's already underneath getting fucked , try harder if she really loves you not suck ohm