Idioms about relationships...

To hit on someone/ to come on to someone: dar em cima de alguém.

Bob hits on every woman he talks to.

Womanizer/ lady killer: mulherengo

She doesn´t get involved with anyone because she thinks men are all womanizers.

Stud: garanhão

Marie would really like to go out with James, even though she knows he´s a stud.

To two-time someone/ to cheat on someone: trair alguém

If I ever find out my boyfriend´s two-timing me, I´ll break up with him without hersitation.

To make up: fazer as pazes, reatar o namoro

They had an arrgument last week but now they´ve already made up.

To make out with someone: dar uns amassos em alguém

Dana met Jim at a party and they made out all night.

To be a third wheel: segurar vela

I´m single and most of my friends are dating, so I don´t go out with them because I don´t like to be a third wheel.

To go steady with someone: namorar sério

We´ve been going steady for 5 years.

To be a spinster: ser solteirona

To be on the shelf: estar encalhada

She´s 37 and she´s never been married. I think she wants to remain a spinster. I always tell her to go out and meet someone but she never listens to me, so I say she´ll be on the shelf forever.

To have a crush on someone: ter uma queda por alguém

Rachel has a secret crush on Eric but she´s afraid of letting him know about it.

To have a fling: ter um "caso" passageiro

Those guys never go steady with anyone. They say having a fling is more fun cause they can get to know a lot of different women.

A catch: um bom partido, um peixão

Paul is good-looking, nice and rich. I think he´s a great catch.

A keeper: (pessoa) ideal para casar

He introduced his girldfriend to his parents and they loved her. They said she was a keeper.

Eligible bachelor: solteiro cobiçado

Michael is single again, but several girls have their eyes on him and now he´s the newest eligible bachelor.

A matchmaker: "cupido", arranjadora de casamentos

She´s met her boyfriend through a common friend of theirs. They keep telling her she´s an awesome matchmaker.

To be free and unfettered: estar livre e desimpedido

Joe dated the same woman for 7 years but they broke up. Now he says he´s free and unfettered to do whatever he wants to.

Wolf-whistle (to): (fazer) fiu-fiu

Construction workers tend to wolf-whistle at every lady that walks by the place.

To carry a torch for someone: pagar um pau para alguém, arrastar um bonde por alguém (nossa, essa expressão é velha em Português!! Vixe!!):

Can´t you see? She´s always carried a torch for you!

To be (way) out of someone´s league: ser muita areia p/ o caminhãozinho de alguém

I can´t believe he´s asked me out! I hope he´s not way out of my league, after all, he´s only dated pretty girls.

To be dumped/ ditched: tomar um fora.

(To dump/ ditch someone: dar um fora em alguém)

Jane has dumped that guy because he wasn´t good enough for her.

Prince charming: príncipe encantado

He´s quite handsome but he´s  no prince charming though.

To be head over heels in love with someone: estar perdidamente apaixonado por alguém

Her son´s head over heels in love with a woman who´s 10 years older than him.

Love at first sight: amor à primeira vista

Do you believe in love at first sight?

To go on a blind date: ir a um econtro às escuras (sem conhecer a pessoa)

I´ve gone on a few blind dates. What about you?

To fall/be in love with someone: apaixonar-se por/ estar apaixonado por alguém

My neighbor got divorced because he fell in love with his secretary.