How do I get my girlfriend/wife's family to like me?

Most people dislike their own family. I'm not most people. In fact, I have two families that enjoy my company, and that I'm rather fond of. My ex's family that lives a meager two miles away, and my biological family that lives in Montana (Mom), North Dakota (Dad) and Oregon (Sister). (For those of you that question my familial neediness, or for those of you that are geographically challenged, that's an average distance of 1390 miles from my hometown of San Diego, California. 1390 miles can also be described as a 23 hour car ride, 18 hour train ride, 19 days of non-stop walking, three hundredths of a second if I was clinging to the undercarriage of Apollo 11 and six years and three months if I traveled via bus. That's a lot of loneliness and quite the distance for an occasional bit of TLC. All those are mathematically proven times, by the way. For the bus I'm accounting for the inevitable Mexican cartel kidnapping in Stockton and the hospital stint that I'll be forced to endure after getting a spork shoved handle deep into my spleen by a methed out hobo that thought I was a five foot eight grilled cheese that was trying to make a break for it.)
Most people wonder why I would want to con my way into being adopted by my ex's family. The "why" obviously stems from my biological family being located so far away. Their lack of proximity essentially forced me to find an alternative family to latch onto for my everyday needs and the continued emotional well-being of my mind. It may seem weird that I've seemingly contracted out what should be a list of my enemies, but it honestly meets Maslow's Hierarchy of Needs for me, so it works. Think about that, most people have a difficult time not disappointing their own families. Meanwhile, I've managed to get inside the inner circle of my ex in-laws. You know what kind of chicanery led to me snowing my ex's extended family into enjoying my company? I didn't projectile vomit all over them while sitting in the back seat of a car ride that was intended to be the start of a relaxing family vacation. Pressure washing your little sister and mother with the waffles you had for breakfast while doing 80 mph down the freeway is a solid way to kill the goodwill of any loving family member. And while that kind of outcome weakens the bond of the biological child, the spew makes the recently canned significant other look all the more appealing.
To be more specific about the situation, I was riding in the backseat with Lyssie and Ruby. My ex's sister and mom. We were headed up to a secluded high desert forest vacation spot called Wrightwood. It was a yearly tradition to go there, rent a cabin and pretend to be off the grid for a weekend. On the surface it was a solid idea for a technology-less bit of decompression. Sadly, it would almost always invariably end with me eating fifty dollars worth of Farmer's market food while binge watching Quentin Tarantino films in my boxers. So the term off the grid might be a little bit misleading. It was more like appearing to be homeless and unhygienic in front of friends and faux family. The trip to Wrightwood is also a freeway-filled three hour drive from where we live in San Diego. Before Lyssie, Ruby and I got to Wrightwood we were slated to pick up my ex, Amber, at the condo she was renting on the outskirts of Cal Poly Pamona. It was a gated community just outside of where she happened to be attending university. What we failed to anticipate when we were picking her up was that she was drunk and hopped up on Vicodin. I'm sure you can imagine what a California Summer, a long car ride, a 1.8 blood alcohol level and a list of pharmaceuticals do to your stomach when you're prone to motion sickness and are sitting in the back seat of a Ford pickup. The pills and Jager Bombs tend to try and plot an escape route through any open orifice they can find.  Luckily for all of us, it happened to be her mouth. To my everlasting fortune, I never got Double Dare oozed. You see, Amber was quite obviously woozy, so I did the only thing an unsympathetic ex could do. I feigned concern and asked if she was okay. She said she thought she was going to puke. I immediately told her to roll down the window and let loose out the side of the car. Naturally, she ignored my common sense plea and just looked at me with all the desperation of someone that could clearly re-taste the two dozen .99 cent Jack in the Box tacos that I'm sure she drunkenly pounded the previous night. After a few beats of non-responsiveness I responded with a heartwarming, "Don't you fucking dare puke on me." She responded by looking straight ahead and layering the dash, terminal, seats and shoulders of her family with what can only be described as a junky daiquiri, or for the mixologists out there, an Amy Winehouse on the rocks. 

That's honestly all it takes to get in your in-laws good graces. I was invited out on these fun expeditions out of a sort of family deprived pity, but ended up behaving myself, enjoying myself and looking like a saint all at the same time. Meanwhile, their own flesh and blood looked like they had been chained up to the hot water heater of a flophouse for a fortnight. That's  really all it takes to acquire a substitute family. Seriously, it's been over a decade since Amber and I's relationship ended and I still have a stocking hanging over their fireplace. So what I'm basically saying is, if you want to be loved, you need to force those that are closest to you to funnel an excessive amount of white lightening and chase it with a forklift-load of Taco Bell. After they're sufficiently stuffed and schnockered you then need to spike their drink with prescription strength medication and reap the rewards of their misfortune for years to come. Or just be a decent human being and let the cards fall where they may. It's a lot less fun that way, but probably slightly less illegal.