Revenge thy name is woman! Good for you!!! Sounds like it should be loud and fun.

Help us a bit with what you might like. Maybe a themed event complete with music, that could be fun.

Mexican/Tex Mex

Sangria
Loaded Nachos or quesedillas as an appetizer
Chicken Enchiladas
Black beans
Guacamole
Flan for dessert

Italian

Wine
Gorgeous antipasto platter
Lasagna
Caesar Salad
Tiramisu

Or you could do a wonderful BBQ style food fest pulled pork on a bun, slaw, potato salad, maybe some ribs, beer.

If we can come up with a menu you like believe me the recipes will follow.

I'll post the same over on Recipes , although the Cooking Forum is much more active, you should try there.

chase's ideas are great because you can prepare this stuff ahead and just put it out without fussing through the evening. Personally I think you should invite more people, in order to get 6 or 8 for sure.
We had a friend who held a ladies only party when her divorce was final--so funny. Great food--lots of champagne. It was called the first annual Lizzie Bordon party. We had a large picture of a guy and did a blindfold pin the tail on --or a variation actually. We had prizes.

I like Chaese's menu ideas. If lasagna seems to heavyI'd do a chicken breast stuffed with artichokes, sundried tomatoes, and shredded havarti cheese. It can be prepared ahead of time then popped in the oven to finish.

Given the nature of this party, I'd consider NOT doing the cooking yourself. I'm guessing you don't have a lot of experience cooking for parties, but even if you do, if you want to appear carefree and having fun, maybe the effect will be enhanced if you are practically a guest at your own party. It will probably cost more, though, but it depends on the menu.

How about sushi? You can order platters from the supermarket in my town, and it costs less than from a restaurant (although there is less variety). If your friends don't like sushi, consider roll-up sandwiches from a nice deli (get a few flavors and cut into small pieces) and a big fruit salad. Anyway, something that doesn't need to be kept hot. I would serve a specialty cocktail or two with that, or to keep it even easier, some white peach sangria (mmmm).

Too bad you aren't comfortable grilling out -- think of the wonderful smell that your, um, neighbor wouldn't be able to avoid noticing -- much more subtle than loud music!

You want to sit and enjoy yourself to show your neighbour that you're having a good time, so what about something that is sort of "buffet" so to speak and a little grilling (shrimp only takes a few minutes and isn't hard at all).

You have your cheese, meat, fish, and veggies with this menu. And the only cooking you have to do at the party is grill the shrimp!

Cheese Fondue

Beef Fondue

Crudites with roasted onion dip.

Chili Glazed Grilled Shrimp

Yield: 6

Marinade

2 limes, zest and juice
1/4 cup sugar
1 tbsp sweet Asian chili sauce
1 tsp fish sauce
1 tsp grated ginger
1/4 cup vegetable oil
Kosher salt to season
Extra limes to grill, cut into wedges
Shrimp
24 jumbo shrimp peeled, deveined, tail on (size 21/30)

Marinade

In a bowl, whisk lime juice, lime zest, sugar, chilli sauce, fish sauce and ginger together. Continue whisking and slowly drizzle in oil. Taste marinade and adjust.

Marinate shrimp for up to 1 hour.

Soak 6 to 8-inch bamboo skewers in water for one hour.

Shrimp

Turn on grill to high. Remove shrimp from marinade. Thread 4 shrimp onto each of 6 pre-soaked bamboo skewers. When grill is hot, grill shrimp about one minutes per side or until pink and no longer translucent.

Grill extra lime wedges for garnish. Season with salt and serve.

I disagree with most of the above....the ex is a neighbor? Right? He's a man? Right?...you need to cook something that will fill the whole neighborhood with lushious smells!
Even if you don't know how to grill....be sure you fire it up and al least pop a couple of meat patties on it to fill the neighborhood with the smell of grilling meat! No matter if you eat them....it's the good smell from the grill that will make him take notice.
As for the actual meal....how about a "grazing" type of meal? I would include chicken winge ( simple, just spread out wings on a foil covered tray and drizzle on bottled "wing sauce"....bake at 375 for 20 minutes, turn them over, add more sauce and bake another 10 to 15 minutes until browned)....be sure you have your vent fan on to waft the wonderful smells outside!
A dish of Italian beef ( recipe here under "seasoned beef") lots of sandwich buns, a bowl of potato salad, bowls of shrimp, lots of fresh veggies....champagne! Even cheap champagne has a cork which pops and yields a wonderful party sound....you can even aim the cork into s meighbor's yard!!
Have fun! And remember, it's all about the smells of a party!!!
Oh....and don't forget tos tring lots of party lights and Japanese lanterns to show it's a party....to the neighbors!
Linda C