Situation 805: ” Is him being unfaithful my fault?”

Hello! So last week my husband admitted to being unfaithful. He cheated with an old co-worker of his. He said he cheated because we have been married for a long time now an he felt like he needed something exciting and new. He tells me that he loves me and he regrets doing that and it was just about the sexual relationship and nothing more . He said he didn’t have feelings for her. He asked me if I could forgive him. I did end up forgiving him because honestly I feel a bit guilty and responsible for him cheating. Should I had done more in the bedroom? Is it strange to feel this way? Has anyone been through this? Is this my fault?