Have I been lied too?

A couple of months ago my husband told me something that broke something inside me... a little back story... me and my husband got married almost 2 years ago and became open like 4 months before getting married. Well a couple of months ago we were talking about us being open revising some rules we had so that it could fit us better and he told me "the real reason I wanted us to be open is so that I could cheat without it being cheating." And I looked at him like what in the actual fck... I brushed it off cause I thought maybe he was joking... I bring it up again to see if he was fcking with me and he said no that's the truth... and I honestly it broke my heart.. I don't know what to do cause I still love him so much but like it feels like he lied to me because of why we became open, I thought it was so we could explore and learn new things as a couple and separately... this has been swirling around in my head and I've pushed it back but it's bothering me a lot lately...
Have I been lied too?
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