Going to tell him how I feel...

I am a 29-year-old woman and have fallen in love with my mentor. I know nothing can come of it because he is married, but I can’t get him out of my mind and don’t know how to manage. My work with him ends in three months and I am considering having a heart-to-heart with him and telling him how I feel. I know this will probably mean not working with him again because he won’t be comfortable with it, but I won’t be able to move on if I don’t have that conversation. I don’t want to regret not being honest about my feelings. Is this a bad idea? Should I just assume this is a waste of time and cut off all contact until I am over him?
You appear to be very clear-eyed about your situation and why there is no possibility of any future with a married man. At the same time, you feel the need to express your feelings, when it can cause awkwardness at best and, at worse, the disruption of a professional relationship. It’s okay to have feelings for someone, but the point of knowing where things stand is to acknowledge and accept that there are boundaries in place that make a relationship possible or impossible. Ask yourself what you really hope to accomplish by telling him how you feel, knowing that this conversation has no positive outcome. If you still feel as if you must speak, do it with your eyes open, knowing what the consequences may be.

My boyfriend thinks it’s okay to toy with my emotions and does it because he knows I won’t leave him. How do I get him to change?
If someone who claims to love you is wilfully causing you pain, this isn’t a healthy relationship. It’s also not a sign of real love or mutual respect, because you and your feelings are being taken for granted. This is a red flag because the onus of trying to change him isn’t on you.