I’m worried my bf is a pathological liar

Last year I told my bf that I am in a stressful amount of debt and I didn’t think he would tell anyone but a week ago I saw his phone that he was getting texts from his mom asking about how it’s going with me paying off my credit card and her saying a person has to earn more money than they spend. He doesn’t know I saw the messages but then today when I asked him it he ever mentioned it to his mom he said he never did and he was like “ oh that’s really personal, I wouldn’t do that..” and then he told me he “would never lie to me about anything” . Now I don’t know how to feel because he obviously lied to me about this since his mom knows about my situation. And now I’m wondering if he lies to me about other things too. The other day I asked him about it again and he said that he would never do that to me. And when I brought up that my ex would always lie to me he agreed with me that it was disrespectful. The other night I admitted to seeing the texts and he just got really upset with me which is completely understandable because I know what I did was a huge invasion of privacy and that was wrong of me. But then I told him I saw the conversation with his mom and he was like “oh really? Okay show me” and when I brought up the messages on his phone to show him (which were all in Portuguese but I had translated so I clearly knew exactly what they were saying) he denied it and said “oh you don’t even speak the language , she was giving me financial advice, I don’t ever remember telling her about your debt” and I just felt so confused as to why he was making up a story when the evidence was right in front of both of us. I don’t even care that he told her because maybe he was just concerned and needed advice. it’s the fact that this is the third time he’s lied to me. I was really upset so I was crying and then he was like “ you’re acting as if I cheated on you” and then kept saying “oh I never told my mom about your debt… did you?” And then we would say things like “oh that’s really humiliating that you think I’m lying to you, you know that?” I don’t understand why he couldn’t just be honest even after I told him I wouldn’t be angry with him if he told his mom. I’m so worried that he could possibly be a pathological liar.. it breaks my heart because I love him and care about him a lot. I don’t know what to do. Is it possible for him to really love me even after lying to my face? My mom said I should really think about it it’s worth breaking up over. Because she knows how supportive he is of me, he even brought me to the doctor the other day because I found a lump in my breast and supported me and was there for me. He kisses me in my sleep all the time on the forehead so I think he cares about me. But this situation is making me rethink everything and it’s making me so anxious and depressed. How should I deal with this?