Is this pathetic and/or should I tell my psychologist?

I'm 14 and I come from a backgroung of people with mental disorders, hard lives and psychotic quirks, but I have always kept it together and never let it bother me. Until a year ago I went out with this guy, and he hadn't ever kissed anyone and neither had I, and he asked me constantly if he could kiss me, and I never knew what to say even though I wanted him to, so I always shruged my shoulders. One day after we'd been going out with each other for 3 weeks, filled with our happy, platonic, love, he kissed my step sister. I have three step sisters who are all biological sisters but one lives with me and two live with their mum and I only see them at school. He kissed one of the ones who dont live with me. After complicated arguements and alot of tears from both of us, we broke up. It hurt so much and I know it's normal for teenagers to have **** like that happen, but after that I just couldn't cope with anything anymore and I don't let people talk about my family problems. That was a year ago, and I'm still not even close to over it, I'm over HIM but not what happened. Last week I went to the doctors (for an "unrelated" reason) and was refered to a psychologist for further tests and CBT (cognitive behavioral therapy.) I was just wondering should I tell my psyc about that insident or is it not worth talking about? I mean I know it's pathetic and I should get over it, but it's been a year and there's not a single moment when I'm not thinking about it, (I think about other stuff to) It's what keeps me awake at night (crying usually) and I don't know,I just wanted to know should I stick to family and life issues when I meet my psychologist or is it worth mentioning my sad excuse for my F**ked -upness?