Is it normal, at a much older age, to fantasize about being molested.

starting when I was around seven years old, my brother who would be about 10 maybe 11, had me play with his boner. He would also have me lay on the bed naked while he laid on top of me and dry hump me. I wasn't quite sure what we were doing, but we were laughing and having fun and that was better than being ignored or picked on by him. He would have me play with him quite often and over time he had me perform oral sex which was fine because we were laughing and playing together. the first time we had anal sex, I remember Being naked and lying on my stomach on the bed after my bath watching TV. He climbed on top and started humping and then it slipped in. It did not hurt, but felt strange and I remember us both laughing really hard. He would screw me quite often after that, or have me give him a blow job. When I got to be around 10 or 11, I did not want to do this anymore, but over the years He had gotten a little mean. It got to the point where I either had to give him a blow job Or screw him or get beat up. When I knew that he was in a Bad mood, there were times that I would ask him to Screw me or ask if I could give him a blow job In hopes of not getting beat up. it all stopped when I was about 13 or 14. I am way much older now, married with children, and close to a year ago I started fantasizing About the things we used to do, especially the anal sex. Am I really demented or is this normal?