Am I wrong for how I feel?

So me and my boyfriend now ex were together on and off for 4 years and it’s been a really bumpy road. I went through his phone while he was sleeping and I came across him messaging another woman and there was multiple pictures of her sitting on the toilet followed by shit pictures from her.... They were also suppose to meet up for a “session” as per the text messages.

I took a picture of the messages so I can have proof of it on my phone and did not mention it until days later. He confessed that he has a fetish dealing with feces and I am totally not comfortable with that so I broke up with him. How can you live a double life and hold secrets like this. Am I wrong for feeling this way?