How should I tell my research mentor that I am considering leaving the program?

[hlsny]

Before I started my PhD, I did research with a professor my school. I really enjoyed the project and the group (the project itself is not based at my university,) and we made plans to expand it into a possible thesis. However, I am extremely unhappy in my program at school. I have been debating on whether or not staying in the program and being miserable will be worth it in the end to continue my research, but lately, I am feeling that it is not. My research mentor has invested time and resources into me, and she is under the impression that I will be continuing a fairly important project for the group. How should I tell her that I am seriously considering quitting the program? Even if I do leave, she gave me a great experience and I don't want to burn any bridges.

[Sigaba]

Before having such a conversation I recommend that you have it clear what you want to do and why. (Not knowing is fine, too, just know that you don't know.)

You outlined some of your issues with your program in this thread :

Would you be willing to talk to your mentor about addressing any/all of those issues?

If she offers a silver bullet that addresses one or more of the issues, would you stay? (If you don't know, don't commit until you have time to think things over.)

A point to consider. Give careful thought how you frame your state of mind. "I want to be happy" is an objective that means different things to different people. For some, happiness is less important than achieving other states of mind.

If your mentor falls into this group, you may not receive a response that you find especially helpful. For example, she may give a response with the intention of motivating you but may instead cause you even more pain. If the conversation takes such a turn, have within arm's grasp a few tactics to change the direction of the conversation or to cut the talk altogether. You could say something along the lines of "I'm feeling attacked right now..."