Holy shit, you guys - this post on /r/relationships

Here's the post for anyone the link isn't working for. I have highlighted MIL-relevant sections:

Hi - thanks for reading my post. Sorry about the length, I'm sort of numb and my mind is racing a mile a minute.

My fiancé "Seth" [23 M] and I [23 F] have been together for 7 years. He proposed to me on our 5th anniversary, and we planned our wedding for our 7th anniversary, which was this past Sunday, Nov. 8th, 2015.

To give a little backstory, Seth's parents went through a nasty divorce when he was 17. His father [45 M] suddenly disappeared, drained their savings account, and stole over $600 in cash from Seth's bedroom. They later found out that he had left Seth's mom [45 F] for another woman. The family was screwed financially and they were forced to move to a cheaper place, an hour away. Seth ended up dropping out of high school to work full-time so he could help support his younger sister [21 F], and his mom picked up a second job. His father never made any attempts to reach out to his children during that time.

Seth and I ended up moving in together in April 2014, and needless to say, we were elated to be finally getting married after 2 years of being engaged. We planned a relatively small ceremony and booked a beautiful venue. I had friends traveling from my hometown, 800 miles away, to attend our wedding. Seth even had some friends coming from his home town as well, and everything seemed to go pretty smoothly with the planning.

Well, 3 days before the wedding, Seth's mom asked to meet with us at her home and announced that she and her ex-husband were getting back together. Seth and I both agreed that their relationship is their business, but he made it explicitly clear that his estranged father was not invited to the wedding. His mother seemed sort of uneasy with that news, but she agreed and dropped the subject.

As we were setting up on Sunday, everything was going great. The ceremony was set to start at 5:30pm, and the reception at 7:30pm. As we were approaching 5:30, my matron of honor ran into my changing room and told me that she counted one extra guest. I sent my SIL to go make sure the count was accurate. As we were waiting on her to come back, we heard a commotion outside and my matron stepped out for a moment to see what it was. She told me that Seth and a guest were down on the ground, fighting.

I ran out, and sure enough it was Seth's father. All of his relatives were screaming at each other. I told Seth's mother to get her date under control or they would both be ejected from the party. They were still shuffling around on the ground, no one was listening, so I went back to my changing room. My matron came to check on me a few minutes later and I told her to call off/postpone the wedding.

^ [Perhaps I should add that I made this decision because my fiance would not respond to me or stop fighting, despite being asked/told to several times and having several guests try to pull him away. They were determined to keep going. I was the last to see his father enter the venue, and we tried several times to eject him, but Seth hindered our efforts. The venue did not have its own security and I would have had to call the police, which would have led to Seth getting arrested. I did not make this decision lightly!!! I was very much on my own in making it because Seth wouldn't talk to me. He was injured to the point of limping during the fight along with some other injuries and I decided that it would be best if we called off the ceremony rather than subject him to going through with it while injured. It was NOT about pictures and I left my original text to show that I never said that. FUCK pictures. He was hurt, so I called off the wedding.]

Seth was nowhere to be found after that. My friends went back to their hotels and most of them left within a few days. My matron stayed until Wednesday to make sure that I was okay. I had a lot of messages from Seth's relatives that I didn't bother to look at for a while. I went to work yesterday, and when I came back, all of Seth's stuff was gone from our apartment. He left me several texts crucifying me for "leaving him at the altar", he said that I owe him an apology and that he just needs some time to think. His friend called to let me know that Seth is staying at his place.

I do feel terrible for calling off our wedding, but I also felt that I had no other choice. This past week has just been one long, excruciating blur. Just like that, my other half is gone. His whole family seems to blame me and I know everyone back home is talking about it. I miss my fiancé, but I resent him and his family for ruining our wedding. I'm not sure if we can come back from this.

I have since called and left 2 voicemails apologizing.

tl;dr Called off my wedding because my fiancé's estranged father crashed our wedding and they wouldn't stop fighting, now my fiancé has moved his things out and won't speak to me. What should I do?

/r/JUSTNOMIL Thread