A therapist can't change your partner anymore than you can. Each of us can only change ourselves and a therapist can only help you to the extent that you are willing to be helped. However, it takes two to tango -- if you change, your partner's going to have to do something! So yes, it can help you to see a therapist on your own; it may help you change the relationship and it will help you find better ways to live with the things you can't change.