Whew. Now that's a million dollar question. But I'm going to help you answer it because I'm going to guide you towards your inner wisdom--that thing called intuition--which, if you can be brave enough to listen, will help you separate the wheat from the chafe.
First, I see a lot of people breaking up that don't need to break up. They are usually projecting all kinds of malarky from old relationships onto this new person and then breaking up with those ghosts. This is why you probably need therapy. Because you're breaking up with someone who isn't even real. You're likely delusional. Relational trauma will do that. It's an over-active fight/flight/freeze/fawn response. That's why getting calm is the number one relationship skill.
I read a lot of articles and Instagram-quotes about moving on from people who don't treat you like a queen. If you need to be treated like a king or a queen in order to feel loved, your love tank probably has a hole in it that no human being can ever fill. So keep searching for those loyal subjects and move on from them when they act human or imperfect or have the gall to have needs.
But. Maybe you're on the other side of that equation. Maybe you're the partner who keeps on trying to make your partner feel special, loved and valued--and it's just. never. enough. They act insensitive, cheat on you, aren't available, and generally aren't interested in adult conversations about emotions.
So how do you know when it's time to walk away and time to just hang in there and do your own work? I apologize, that's a bit of a trick question: because the answer is always in doing your own work FIRST.
When you do your own work, you won't actually have to do anything except speak how you feel.
An awesome partner will welcome you speaking your emotional truth because they are interested in knowing more of you. They want to be intimate. But a partner who isn't interested in a relationship will be unable to tolerate you doing anything but agreeing with them and/or doing what they want. They will also be unable to tolerate that they might have failed you in some way. They don't know how to live in their humanity.
"Narcissists are very good at finding their 'victims' - the people who don't feel worthy enough of a healthy, happy relationship, and who will play second fiddle just for the sake of being in a relationship. When you've learned to truly love yourself, a narcissist simply cannot operate in your orbit. You will not be able to feed his or her need for adulation and acquiescence at all costs. And you will trust yourself to know when to walk away. That's why, for anyone struggling in a difficult relationship, the fastest path to answer the question, 'Should I stay or should I go?' is always to learn to love yourself. " --Gay Hendricks
That all being said, often, talking and talking and talking will actually drive a quality man away. When I say, "speak your truth," I mean open your posture and your heart space--and tell him what you ache for. Don't tell him what he's doing wrong, tell him how when he wraps his arms around you you feel like nothing in the world can harm you. When I was in graduate school we had a saying: “speak the truth in love,” that comes from the book of Ephesians. Before you speak, always, as much as you can, ask yourself, “am I going to say this truth in the spirit of love and growth? Or fear and destruction?” The tone you use has the potential to either increase the conflict or help you grow closer together.