Break Up Recovery

Hi, I would appreciate help in moving on from a relationship once and for all from any listener/supporter who has advice, aid or similar/relevant experience/insight to share with me. I'm an 18yo female that's been in two relationships with the same person. After breaking up with them the first time, even after three years and throwing myself into AP classes, conservation volunteer positions, being open to new people, getting a summer job and working to improving myself all around, I still long(ed) for that person constantly and felt a little hollow without them. We recently broke up for the second and last time and I'd like help in effectively moving forward with my life. Thanks