Am I at fault?

I am in love with someone who likes to keep a low profile…We had an issue that made us break apart for about 2months and it was cos i had to tell his friend to help me talk to him and he broke up cos he doesnt want people knowing about his private life…We broke apart and got back together about 2months now…Out of anger cos of something he did,I blurted out to someone that he accused me of cheating..He found out and he was really pissed and I tried to reason with him…Not long ago,I bumped into his friend,and he stopped me and tried to ask me if I was able to settle the issue that caused our initial break up and I initially mentioned that he should ask his friend but eventually I said yes and I didn’t divulge anything about my relationship with my boyfriend(probably ex now)…He talked about my boyfriend but I tried to keep the conversation as light as possible…Now I think it was all a set up cos my boyfriend (ex now),called me to ask me about it and he was pissed that I talked about him but I didn’t say anything bad,his friend did most of the talking and I just replied.And i just wished i recorded the conversatuon because some things are being used against me.Is it wrong to have a casual conversation about a person?….Now he says I have a running mouth…How is this my fault please?