Avoid all the meeting places. Do not go to the area in which she lives. Do not go near her office or college. Avoid all her regular haunts. Even if she tries she should not be able to spot you anywhere. Identify the good Samaritans who want you to be in touch with her and cut them off too. They would hinder your plan.
Throw away everything in your room that would remind you of her. The small things she presented you, the cards she sent, and anything that would make you think about her, get them out of your sight. The unsigned gifts can be presented to other friends with a sly smile! This will help you get her out of your system, to forget her, to remove her from your mind painlessly.
Be strong; resist the temptation to demand her to return all that you presented her. It is childish and not worth your while to talk to her about it and to meet her again to get back those trifles. Just forget all you gave along with her.
If you were used to spending a lot of time with her and now if you feel lonely and have a lot of time, plan a new timetable. Spend more time with other friends; find a new hobby or work to do. Start learning something which you always wanted to learn and found no time. This is the right time to do it.
Having time on your hand is freedom. Every one in this world today is short of time. There are many interesting things you can do with your time. Do not squander it.. Learn a new skill, enroll into a new course, and learn to swim or learn the technique of building a fish pond, anything interesting.
You can do one thing that would be really effective. Find a new girl friend. With the experience you have gained from the previous affair, your new relationship will have a better chance of being successful.
If you are afraid of getting involved with a new girl and to go through all the old rigmarole again, just find a hot chick to share your bed and that would really brighten your life.