I (21F) have to ditch my boyfriend (22M) because he kicked my (21F) best friends puppy (3-4mo)

So I have been with my boyfriend for 2 years and he has never ever made me feel unsafe (this is new as of last night). It's important to mention that we both love animals. I have 2 dogs, a cat and he has a cat and a snake. We have been quarantining at his mothers house. My boyfriend has been friends with my best friend for about a year now. She goes to visit (this was her 5th time) and brings her very sweet, well behaved puppy. <br><br>Now, for a background on the puppy. He's a 3-4 month old pup who is very very socialized. He is well behaved (sometimes does normal puppy stuff like stealing socks and running away). I can not stress enough how well behaved this dog is. The puppy is trained already to sit, stay, stop, and leave it. It's insane. <br><br>So last night, the puppy had already learned not to get near a cat (the cat gave him one warning slap in the face on night one). She has a bag she uses to pick the puppy up in when the cat is around and he's scared enough not to go near her. Last night, I was on a work call for 3 hours. The cat and the puppy were in the same room as me. The cat was in her tree and the puppy had free roam. The cat was sleeping. He did not bother her for 3 hours. <br><br>After I get off the call, I leave the room for maybe 15 minutes. In that time, the cat exits her tree and the puppy sniffs her. he was very close to sniffing her face but did not do it and the cat was looking at him. It all went fine. I come back into the room and the cat is in the tree again and the puppy is on the bed next to me. I had a bag of treats next to me and I offered him one (to get him down and out for the night) but he did not want it. When I moved the bag, I had to move my leg off the bed and in doing so, my toes (that were just in socks, no shoes) touched his neck. Now, he likes to play like a typical puppy and he thought my toes were something to play with. He chomped and did a little growl but let go. Not hard, but enough to leave teeth imprints. <br><br>The cat was still in the tree and watched all this happen. She leaves the cat tree and jumps down onto the bed, walks up to me and on to my lap. She did not hiss and spit. She gave the puppy one warning (with her paw) and then left the room. I take the puppy out of the room and leave him in the living room. <br><br>My boyfriend starts yelling from the other room (I did not hear him, my best friend told me what he was saying). Then he walks in and grabs the puppy "like a football" and lifts him off the ground. Not by the collar, by his body, he was in so much pain (the sounds he was making were guttural and in pain). He (my boyfriend) told me to get out of his house and take the dog with me. He then came back into the room to tell me I was not welcomed back in his house. I asked if I could come back for my stuff and he said yes. There was a brief silence and then he said "get out" and punched the wall. He left the room and I never saw him. I am really, sincerely, scared of him now. <br><br>The puppy and the cat have never had an altercation but I understand why my boyfriend is upset. I do not condone his reaction at all. He has always been very calm and level headed. I just don't know where to go from here. I have been with him for 2 years and I planned on marrying him. I am just so confused and I don't know what to do in this situation. I don't know if I am doing the right thing by ending things. What should I do?