Dealing with badly behaved parents at important events?

I love my parents (well at least my mother) but they are…intense to say the least. My father has an untreated personality disorder that often manifests itself in rage, not to mention a myriad of physical health problems which keep him in a perpetually rotten mood. My mom is a stressaholic who tends to dwell on negativity and takes a cocktail of medications which I think exacerbates her tendency to say inappropriate things. Needless to say, they can be very difficult to be around, especially if you aren’t used to them.

I brought my new boyfriend to their house over Easter and he said they made him uncomfortable. My mom did nothing but complain and of course, my Dad was pissed off at everything as usual. I was really disappointed with how it went and I started thinking…

Like most girls and women, I hope to get married someday and have a nice wedding. This might sound silly but every time I see stuff for weddings on TV or pass by a bridal shop I get almost unreasonably depressed because I know they would just ruin that day for me.

I’m not near getting married yet but their behavior is starting to affect me in other ways. I graduated from college in December and have decided not to go back for the ceremony in May because I know they would behave badly that day. Every event or accomplishment I have, they manage to suck the joy out of and just bring the mood down with their soul crushing negativity.

My brother excluded them from his wedding. I’ll admit, it was kind of a dick move but of course they’ve never gotten over it.

Has anyone or someone you know dealt with a similar issue? How do you deal with negative parental energy on important days? Do you just avoid celebrating altogether?