Should I stop being friends with someone who has repeatedly hurt me?

Tony, you present a difficult question of worrying how far to compromise your values in the effort to keep a friend.  This kind of dilemma is often related to insecurity when it comes to self-confidence and self-esteem. To ignore this challenge equates to being complicit in something that goes against your core values.

Now imagine if you were able to feel fully prepared to respond to this problem; if you were presented with the necessary skills and strategic steps to reach your desired outcome.  DBT or Dialectical Behavior Therapy skills can assist in gaining a detailed understanding of how to more  effectively communicate the point you are trying to make.  I will outline some of the key components here, but if you have a BetterHelp therapist, you can also request DBT worksheets that pertain to interpersonal effectiveness skills. 

"Effectiveness" in this case has to do with obtaining the changes one wants, maintaining the relationship, and maintaining your self-respect.  There is a slightly different emphasis depending on which aspect is most important in a given situation.  You can ask yourself, in this situation, which goal rises to the top: reaching a specific outcome; keeping the friendship; or prioritizing your self respect no matter what.  Additional questions help guide and discern whether it is a good time to confront the issue/broach the conversation, whether you have done adequate preparation, and whether the request is appropriate to the relationship.  There can also be factors that take away from effectiveness, including lack of skill, worry thoughts, emotions, indecision, and circumstances of the environment.  

In DBT the acronym DEAR MAN, stands for describe; express; assert; reinforce and mindful; appear confident; and negotiate.  In other words, you would: 

1)  Describe the situation.  Tell the person exactly what you are reacting to.  Stick to the facts.

2)  Express your feelings and opinions about the situation, using phrases like "I need; I don't want."

3)  Assert yourself by asking for what you want.

4)  Reinforce or reward the person ahead of time by explaining consequences.  

5) Mindfully keep the focus on your objective.  Don't let yourself be distracted.  If needed, keep expressing your opinion over and over like a broken record.  Don't respond to attacks.

6)  Appear confident, effective and competent by using a firm voice and refraining from apology.

7)  Negotiate and be willing to give, in order to get.  Maintain your position, but offer to do something else or to solve the problem another way.  Focus on what will work.  This can include turning the problem over to the other person by asking "What can we do to solve this problem?"

When a person's primary goal is to preserve the relationship, the additional skills can be remembered by "GIVE."  

1) (be) Gentle, be courteous and temperate in your approach, with no threats or judging.

2)  (act) Interested, be patient.

3)  Validate or acknowledge the other person's feelings and difficulties.

4)  (use an) Easy manner in listening to their point of view.

When the overriding goal is to maintain your self-respect, then a way to remember the skills is "FAST."

1)  (be) Fair to yourself and the other person.

2)  (no) Apologies, be clear on what you believe is the moral or valued way of thinking and acting, and stick to your guns.

3)  (be) Truthful, don't act helpless when you're not and don't make up excuses.  

Sometimes there are conflicts in priorities that make it harder to choose an effective approach.  You can ask yourself questions like: 

What specific results do I want?  What changes do I want the person to make? 

How do I want the other person to feel about me after the interaction?

How do I want to feel about myself after the interaction?

Being prepared with a skillful approach can definitely increase the odds of achieving the outcomes you hope for, without any negative consequences.  It may feel a bit contrived to have to think through all these factors, but once you become more familiar with the concepts, it becomes second nature.

I support you in your search for a stronger sense of self and hope you can find some helpful ideas here.