They have emotional support. It can be friends, therapy, groups, or bare minimum some personal resources that they can access if things get rough. It’s impossible to be someone’s only support. They will drag you down with them.

To add to that- they have a positive and receptive view of therapy.

I don’t know how to answer this properly, I’ve only had 3 serious/long term girlfriends and I married the 3rd nearly 20yrs ago.

I’d have to say being down to earth, farting on the 3rd date and just laughing about it.

She’s always been my best friend, one of my dickhead mates I can let my hair down around and we can both be ourselves, all day, every day.

Green flags:

Their smile.

Their obvious kindness.

Their big heart.

They make you laugh.

They drive.

They ask you to drive.

They have friends that you like.

Your friends like them.

They read novels.

The play a musical instrument.

They speak another language.

They can ride a bike faster than you can and you think you’re kind of hot shot about that.

They openly tell you that some of your habits are unsavory. You know they are. How courageous of them to mention it.

They like you anyway.

They can make chocolate chip cookies from memory and do like for no reason.

You like their family.

They don’t like your family but then again neither do you.

34 years later the two of you not only love one another but find things to like about one another every single day.