My boyfriend 22M dumped me after 5 years, because I 21F accused him of “lying”, I don’t know what to feel?

I don’t know really know what to believe anymore. I am feeling numb. I would like to believe my partner is a logical individual and he makes a great partner, he really exceeds my needs. However I’ve been noticing patterns that are bothering me.

My boyfriend has a tendency to make huge statements without thought or any real “evidence”. There have been two separate occasions where he has claimed people in his immediate family verbatim have cancer, 100% have cancer and they didn’t. The story always ends up changing, and he blames other factors like the medical institution or a mishap. He has leveraged these stories as a way to fish for sympathy. He changes the stories and they don’t really make any sense at all. He has told the same stories to my mother, and my mother had mentioned something wasn’t quite right. He also made smaller statements as “jokes” but longed them out for way too long & tried to act convincingly, like he got pulled over or crashed his car, which I didn’t find funny to receive such calls. Now I know for an outsider this may seem obvious, but he does it infrequently, so Im very confused whether this is his genuine character or just coincidences. He told mocked me calling me an “investigator” for asking questions.

Now – My boyfriend recently moved housing, he told me he had to get his dog put down in order to move, because the temporary accommodation they were moving to (for just 2 weeks) wouldn’t allow the dog to live there. Him and his mother said that they couldn’t put him in a dog hotel or kennel for those two weeks, because the dog was previously abandoned and had some PTSD and that the kindest option was to put him down.

This didn’t make sense to me, the dog was 12 years old it was his childhood dog. I didn’t really internalise it, based off huge statements he has said in the past I almost knew there was no way that dog was dead, I just kept quiet about it despite he told me the dog was now dead. I saw texts from his mother saying it was 100% put down and how upset she was because she didn’t have a choice.

Less than a day later he sends me a picture of the dog and its alive. He gave me some BS story that sounded borderline illegal, something about taking tablets and the dog wasn’t dying, but the tablet he named was a anti allergy one for people? He admitted his mother lied. I tried to tell him it was bothering me that he would make such huge, worrying statements and they were never true. And I wanted to give him the benefit of the doubt and he had accidentally relayed information from his mum (she has a pattern of lying) I didn’t want to accuse him of lying but I honestly never know if I should believe the things he says. In return – he told me I was a disgusting human being because I never asked how he was when the dog was put down (it wasn’t). He said that we are done for good and there is no going back from this and I am a horrible human being and pretty much one of the most vile people ever. He said some pretty hurtful things. I’m not sure why he doubled down on this knowing the dog is actually alive. He told me I was terrible for trying to “debunk” things rather than being a good partner.

We have been together 5 years, I honestly believe he was looking for an excuse to break up with me because weeks leading up he had been so irate and blew so many minor things out of proportion, I was blank. I don’t know what to think at all.