Need major help: Boyfriend with BPD

Hi everyone,
I have been dating an undiagnosed borderline for 1.5 years. I'm in my mid-20s, graduated college with a good job. He's early 30s, didn't finish college and working for his brother. Ever since the beginning, my intuition has been telling me something is off. One day he's all about "I love you, can't see myself without you" and sending me flowers and literally feeding me at the dinner table to the next day either disappearing or appearing to resent me for absolutely no reason. He has a drinking problem. He has problems with his family. He works for his brother and sometimes fails to show up to work because he was up all night drinking. He would quit work about once a month and have plans to start his own business and I would even help him with the website, logo and EVERYTHING for him to blow off our conversation to finish it so he can go drink with his friends.

As to our relationship, he's verbally and emotionally abused me to the core. I literally saw him cheating in front of me after 3 months of seeing each other and one week after my best friend died. After many apologies and promises and excuse that "we weren't really together," I took him back, although, I could not swallow the fact that he told me he met her a week BEFORE he met me, only to find out 17 months into the relationship that he had met her the same day I saw him with her, it was only a one night stand. I caught him texting other girls, took our his ex for lunch and gave her a ride to work when we were taking a break, asked another girl out to drinks, which she declined, found him texting the same ex "I miss you so much baby sad " and all of his excuses are "I'm so sorry, I messed up, we were taking a break so I was doing stupid stuff." I moved to NY for a great job. When I visited, he's flaunt in front of his friends "my girlfriend works for .... and lives in NY" to show me off because all of his friends (old and new) always praised me to him and behind closed doors, he would yell and throw in my face "just because you work for ..., doesn't mean you're better than me" when I literally NEVER even talk about work with him. He admitted to make me jealous on purpose just "because I need a little push every now and then" and he would laugh, although I've told him THAT'S the reason we have trust issues because one second "it's just my friend texting me" and the next he's saying she spoils him and threatens to call his ex at 3am when he's drunk. Any time I'm going though a bad day with work or stress, it turns into a pity party for him that HE'S Sooo stressed or has work problems so I end up tending to him and forgetting about mine, or he would just ignore me the rest of the evening and would NEVER be there for me. Any time I'm going through a death, stress or something, he's literally never there and sees going out with his friends is more important.

He learned that when we are going through problems and I get upset with him and need sometime, saying certain things, adding skanky girls on facebook, or accusing me of cheating (which I would never even think of doing to him) would get me back to defending myself and talking to him again. So he started using that against me. ANY time I'm upset, it starts with "his stomach hurting from last year's surgery," to his apologizing bc he's so stressed and if I don't respond, he's start accusing me of cheating or adding trashy girls on FB to upset me. Sometimes it's him begging and pleading for me to answer him. Sometimes he would just not communicate with me for 1-2 weeks only for me to find out he's been partying a lot (as usual) and hung out with 1 of his exes who's his "best friend" now. I started not even reacting at all to his temper and he amped it up to even accuse me of some things that could seriously get me in trouble which I NEVER would even think of doing and literally telling me, "you have until 6pm to tell me the truth" and if I don't say anything he'd text me "so you'd give up our relationship instead of telling me the truth" only to admit the next day that he KNOWS I was telling the truth and that he's truly sorry. The last 6 months consisted of screaming matches, him putting me down for NO reason literally telling me "I'm nothing", throwing stuff at me, even when I visited his apartment I'd find holes in the walls or huge bruises on him saying "oh my friend and I were playing and started fighting" or seeing who can hit the wall the hardest... It would be 3-4 different stories for the walls, bruises, cuts before I give up trying to see which story is true.

As you can imagine, this guys has pulled every trick on me and somehow I still felt bad for him because inside I know he has a good side in him and has so much potential but he's his own enemy. His own friends have told me MANY times to leave him to the point they gave up on giving me advice. I'm tired. I'm exhausted. I stopped talking to him 1.5 weeks ago because I cannot handle it. I completely changed. Without him in my life, I literally have ZERO problems, I'm very outgoing and everyone tells me my true self only comes out when I distance myself from him.

Now, he is begging for me back, apologizing, saying he messed up, I love yous, sending me songs, asking me if I still love him, etc. The warm side in me wants to reassure him "I'm not with anyone, I will always love you but I cannot do this anymore" but a side of me says "You've done that MANY times only until you get comfortable to where he could catch you off guard and start manipulating you again." I know he would be like this for 1 week max and then we're back to push and pull. Please please help me and let me know what you think. I'm stuck. I 10000% do not want or see myself with him and my family and friends would never accept him. I know this seems OBVIOUS but anyone who's been in my shoes, manipulated, verbally and emotionally abused, you'd know the cycle. I just feel really bad for him because he really has no guidance or good influence but I feel like he has no one now because they've all just given up on him.