Hi, I'd like to help you with your question.
You will know that you need to end the relationship if every possible effort has been made to work on the issues and it still cannot be resolved. This is rarely done. Most people will do what they think will work and when it does not, they end the relationship. They are either not aware of the help available or they choose not to utilize it.
The only two exceptions to this is when one partner has had an affair the other partner has a choice to try to stay to work it out or leave, or if there is abuse in the relationship of any type (emotional, drug and alcohol, or physical). If there is abuse, the relationship should end without hesitation.
Whenever two people are together, there is a reason they were attracted to each other. It may be for love or it may be for dysfunctional reasons. But whatever it is, the couple is together over anyone else. So there is a bond there. That bond remains but what happens is other things interfere, such as bad habits, harmful behavior, and other acting out by one or both partners. This affects the relationship and the bond starts to break. That is why you will find numerous options in society for repairing relationships- it is rare to find a couple that does not have some conflict or another.
Your choices for help in your relationship range from retreats, therapy, self help books and seminars. The trick is finding what works to break through the issues of your relationship and helps you as a couple re bond. The solution also has to something you can build on so the same issues do not return.
If you have any other questions, let me know.