I'm glad you are reaching out via e-mail to the help center.
If you like Cagney and Lacey, you might also like the Stephanie Plum series by Janet Evanovich. The first book is called "One for the Money." They are fun to read.
http://www.amazon.co.uk/exec/obidos/ASIN/0140252924/
The fact that you are obsessing on one person is a problem. Here's something interesting I found on this.
http://easyweb.easynet.co.uk/simplepsych/obsessrel.html
Some people have a history of relationships whereby they are treated badly, or treat the other person badly. It seems to happen to them again and again.
If you see this pattern in your relationships then their is more than a chance that there is a problem in you. You are very unlikely to have just been unlucky.
People in this situation have got to break the cycle of bad relationships.
This book was recommended on that page.
http://www.amazon.co.uk/exec/obidos/ASIN/1576830535/
You mentioned that your mother did not approve of your infatuation with the tutor. Would you say that your mother treated you badly in your life? Who are the people who treated you badly?