In general terms, most relationships start with that twinkle in the eye beginning. You see this other person for the first time, and you feel a connection. You begin the mating game...the feeling out process. Dating, kissing, maybe love making. If you pass that initial stage of not going to work out, you continue on. Your thoughts are of spending your life with this other person. You learn a little more about the other person, day by day. If this all happens as your first love, you're not really thinking of and planning for the perils of life, because you're too busy with dating and planning for a future, and having fun etc. If you decide to make it permanent, the real journey has begun. You have no idea of the future, even if you pretend to yourself that you've got this. Just because you watched your parents grow up, or know others in relationships, that doesn't make you an expert.
Children, finances, home ownership, education, jobs, family, friends, and the fact that you are both different people - none of this ever really sets itself up for you on a silver platter, even if you believe so. You hit the road hand in hand all happy, and you want to believe all you see is a long straight road ahead. Then you hit the first curve in the road where you were probably going a little too fast so you slip a little as you hit that curve. As you right the ship, another curve. Then another, and another. And some point you begin to realize - the road isn't going to straighten out again, but instead, the road will always have that next curve you cannot see around.
Some relationships are able to maneuver through each of those curves, where both participants somehow are able to grab the wheel together. Sometimes you get scraped up in a curve, but still make it out. And sometimes, just one big crash and its over.
Strength, prioritizing, balance, understanding - these are some individual characteristics that ultimately prevent you from crashing. You don't really know who you are or what you are made of until you hit that first curve. How hard can you hold the wheel and keep yourself grounded to life's road? You only answer that upon exit from that curve. You learn. then the next curve. Different circumstances, and you learn again. Some curves may just be too sharp and you crash...separation, divorce - the relationship is over. Maybe you're lucky enough to have been able to make it through every curve unscathed. But in my own experience, I believe a majority and up in life's emergency room from time to time, getting bandages and medicine in order to be able to get back behind the wheel.
All of this is dependent on each partner individually, and both partners together. Without both working in unison, you will crash. Love, soul mate, best friend - these are re-evaluated each time you enter one of those curves. It's a road that never ends. It's bumpy, it hurts, it damages - but it can also ultimately be happy and satisfying.
I've been on this road for 36 years. I've been on a section of road for over a year that feels something like this:
I'm still maneuvering. Treacherous. It seems a crash is always about to happen. But to this day, still driving.