I think that's not the point of the marriage.
It has been said that you can depict romance in drama or a novel or film, but not marriage. Romance is dramatic: the two people have to make choices about whether to act on their feelings and overcome obstacles, and then when they finally come together you have a high of satisfied expectations. Romance has to have a plot arc: the two people come together or they fail to come together or they circle around each other indecisively. Marriage is not dramatic: the quality of the marriage depends not on dramatic choices or on overcoming obstacles but on little ongoing interactions. You can show the characters having healthy interactions or unhealthy interactions once or twice, but what makes a marriage healthy or unhealthy is not one or two interactions or ongoing arguments handled well or badly, but the trend over time.
But when you get into an ongoing serial storytelling like a soap opera or a comic romance doesn't work as well. Romance is a hit: you see the couple work their way towards getting together. But then, they're together. So for the sake of drama they have to split up and then they get together with other people, but it's just a little less easy to care because it didn't work out the last time, and then they split up and get together with someone else again, and again it's harder to care because they're not going to last.
Marriage on the other hand can be depicted in an ongoing story, because you can just see them supporting each other or failing to support each other in a difficult patch, and there doesn't need to be an arc with a shape to it for the whole of the marriage.
What MJ/Peter marriage fans want to see is not Peter and MJ getting married every five years or even getting back together every five years. We don't want to see the marriage again or even Straczynski getting them back together again. We want to see them just getting on with dealing with the stresses of superhero life together.
FFS this is Marvel. Reed and Sue are right there. The problem with the Fantastic Four is that Reed and Sue are married, said no Fantastic Four fan ever.