After being in a second marriage for 2 years (relationship for 5), I'd say the secret to making it work is simple, you have to be able to forgive.
I saw an elderly couple on tv one day who had been married for 77 years and when asked how they had stayed married so long, the wife didn't hesitate...she simply said, "You have to be able to forgive." and, after having been in a first marriage for 25 years and now a 2nd marriage for 2, I would totally agree with that statement (and I thought to myself...yea...forgive over and over and over...).
Dh and I went to see his parents last weekend and as we sat in church, I saw my FIL with his arm around my MIL and I thought how wonderful...after 54 years of marriage to see that. My MIL has shared many things about their marriage to me (we are great friends) and it has been ANYTHING but an easy road and she has forgiven things many women wouldn't for the sake of love, family, and committment. My parents are the same...married 57 years and not easy. I guess dh and I both learned committment from our parents because BOTH of us have wanted to run out the door screaming more times than we can count due to the issues many of you know we've had. But, we're hanging tough and dh and I both thank our parents for that. They taught us when you love someone and take those vows, that you don't run just because things are difficult. You may WANT to (as I did this past summer), but, if you want the marriage to last, you have to tough it out. Make no mistake. I know there are definite "deal breakers" and would leave if those things were the case. Dh knows what these are as well. Dh and I have learned new things about each other in the last 2 years and some things we really don't like about each other, but have come to accept because we want our marriage to last.
Dh just recently lost his job, so we have yet another hurdle to stay strong through. Dh's parents had to move from their hometown to a town where they knew noone and had to start over...in their 50's. I reminded dh of this recently when he talked again about wanting to stay here...which may not be an option as the job he has has few opportunities here. I just keep telling him we are survivors and we will make it through this as well.
Just wanted to share my thoughts of the day. :) I hope you all have a wonderful Thanksgiving!