Well, I will hit my 9th year wedding anniversary this year (11 years together), and as ahugeopponent of marriage, I'll chime in!
First off, echoing what everyone here is saying, if you two are fighting/unhappy now (even with your recent post of an emotion filled make-up), chances of you two doing 50+ years together seem ludicrously small. A couple of things I don't think you have mentioned yet; How long have you two been dating / How long have you two been living together. I'm getting the impression that you haven't been together all that long, and living together for only a few months, am I wrong there?
The reason I ask is because I can not stress enough how different living with someone is vs. dating them. I don't know why people don't get this, but you really have almost no idea if you are compatible with someone until you have lived with them for a while, I would say over a year, closer to two. At that point, you should both have a really good idea of whether this is going to last. My brother in law has been dating a girl for 6 years, he works out of town 3-5 days a week, and they spend around 50-75% of his home time together, but he still had his own place. From all outward appearances they have been happy and making it work for 6 years. He moved in with her in January this year, and they just broke up 2 weeks ago. A relationship that was great for 6 years, over in 2 months living together. I think that's a perfect example of just how much you don't really understand how your partner works, and how you work together 24/7 until you have made that step.
Now, everyone's been talking about how its only going to get harder, and again, I completely agree. I was pretty much great the first 4 years of my relationship, but around then I started getting really depressed and thinking about divorce. It was no one thing, it was just the thousand little things. I wasn't really happy with our sex life, which was a big deal to me, and just about everything she did annoyed the hell out of me. On top of that, she pretty much had no interest anymore in anything I was into, but also had no other interests or close friends, so nights basically devolved into her not wanting to do anything, but not wanting me to do anything either, except "hang out" with her, doing nothing. So, I would come home and we would small talk and have dinner, and maybe watch a movie or something. Then sit around and talk some more, usually me just listening to her talk about work. Then she would go to bed, while giving me loads of shit about not coming to bed with her, and I would breathe a sigh of relief and go hop online with all of my friends and have a fantastic night. We just didn't have much in common anymore, and we both knew all about the other person, and the desire to be around her just kind of left. I didn't want to hurt her, and so I just dealt with it, and was unhappy for a good year.
Around year 5 she decided that she wanted to go see a doctor about her lack of desire to do anything, and her growing depression, and utter lack of sex drive. She got some form of Prozac and within about 6 weeks was pretty much entirely turned around. The next year went by pretty great again, not as good as the first 4, but we were both pretty happy again. We decided to have a kid. She got off her meds and birth control, and got pregnant. She loved being pregnant, she was super energetic and happy all the time. It was a pretty great year. We had our son, and 3 months later I told her I wanted another one (I had initially not wanted any kids, and she wanted 5 or something, we had agreed on 1), which blew her away. This time however she was super unhappy the entire pregnancy. When our second son was born, she went into super depression. Just crying randomly and having no patience with anything, she just wanted to sleep all day - every day. After 6 months of this, something I was assured was natural and would go away, I finally told her that I couldn't keep doing this any more, that she needed to get back on meds or something, or we were going to end up divorced. She got back on the meds, and while things didn't go back to crazy good, it became tolerable.
Cut to current times. Jan of last year she decided to go fitness nuts. She joined a gym and a running team, and that's been great. Not only is she not on any meds anymore, she has a group of outside friends, and something she is really into. We both love being parents, and our kids are great. Basically, everything is going as well as can ever be hoped for in a marriage right now.
So why then, am I totally against marriage?
For me, the negatives, still outweigh the positives. If you asked me to write down all the things my wife does that make me happy... that's a pretty short list. All the things that make me unhappy/annoyed/frustrated/upset? That is a much larger list. I just can't help, every time I come home from a 15 hour day at work on her day off, and the house is a disaster going "You know, if I had my own place, this would not be an issue.", or at any argument going "Why am I even here? If I just left I wouldn't have to deal with this.", or any of the other 5,000 minor things. And that's the big issue, there are no major problems, just always a never ending stream of minor ones, and she is totally content, it's just me with the problems, and that's why I can really only see marriage lasting in a few select situations.
1. You are both completely selfless forever, you just get along, and let every potential problem slide off at all times. I imagine this is insanely rare.
2. One person is willing to make sacrifices or be uncomfortable for the other ones happiness, maybe not being that happy themselves. The situation I find myself in.
3. Who cares about happiness, some guy says God says divorce is bad, so we better not get divorced, you know, just in case.
So, after being married a third of my life, I can only really see cons in marriage. The pro is that you do what people expect, and who knows, 1 thousand question marks. The cons have already been listed by 40 people, so they should be pretty clear, but let me give you my internal struggle.
I love my wife, she's a really good person who deserves happiness, I just don't really want to be the one sacrificing my life for her happiness. I'm selfish. I just want to be happy myself.
I love my kids and love being a dad. I don't want to lose that.
If my wife came home today and told me she had met someone else and it was over, I think I would be relived and happy about it. That pretty much tells me I'm no longer really invested with her, I just don't want to crush her world.
I had thought maybe I would press for divorce after the kids grow up, but by then my wife will be in her 40's and I would feel like the ultimate bastard for staying with her throughout all the years she most easily could have found someone else.
But, if I leave now, I will probably end up super broke, in a shitty apartment, paying tons of child support and getting to see my kids on the weekends.
So, there is a marriage success story for you. Even with all that said, my marriage isn't truly awful or anything, I would say its better than 90% of the people I see. We never have screaming matches or throw things at each other, when we do fight its usually pretty passive aggressive.
So yeah, I tend to think my marriage is way more viable than most, and even then don't think it really works.
RETHINK IT.