Kerver, step-perenting isn't easy, by any means. I have been to hell and back with my husbands' children but because I'm in love with him and figured that they've got to grow up sooner or later (and it's been later more than sooner with each of them), when he proposed, I accepted. The great thing is, all three kids adore me. The tough part is, they were brought up by someone else-sometimes it felt like a pack of hyenas- with ideas and morals and processes completely different from your own. That's when the clashing begins. And your poor husband is in the middle.
If you survive it, the rewards are many. When my steps let me know how grateful they are that I came into their lives, it feels very nice, indeed.