Count me in. My DSS is almost 16, and DH and I have no children together. I'm really torn about whether I want any at the moment. Sometimes, I really do, as I've always wanted them, and other times I just don't know how it'll work with our current set-up.
It's been a real eye-opener for me. I've been lucky, as I don't have the issues that some posters on here have, although I have sometimes struggled to work out what my role is, and there have been times when I've found it tough, even though my situation is not a bad one. I think you have to be so careful about what you do and don't do as a SM, and even then probably don't always get it right! DSS and I get on well - he's pretty quiet and I like to leave him and his Dad to do guy stuff together as his Dad is, if we're being honest, the main person he wants to see. As another poster said upthread, I tend to leave the parenting to DH, as that is his job, and not mine, although I will always support him, and do give my opinion on any issues as they arise. I like to have a chat to DSS about how things are going, but I've let him set the pace, if that makes any sense? I don't want to be pushy or force stuff on him, so try to be pretty relaxed about things.
DH and his ex have a pretty good relationship most of the time. However, I did find it difficult having to consult a third person about potential holidays, etc. Before I get flamed, I realise the ex is the mum, and would not want to step on her toes at all, but I think she can sometimes be unhelpful when we're trying to plan stuff. Conversely, when she wants to change contact arrangements, she tends to do it the week she wants the change to happen and expects flexibility. Would just like a bit more consideration from her sometimes, and I tend to get frustrated when mums on here then get incensed that the SM would even dare to have an opinion (and I shall now breathe).
Lastly, wanted to say that I think this forum is fantastic. When I first became a SM, I didn't have any friends or family that had any experience of step-families, and I felt really out of my depth. I still do, but the support and information from the ladies on here are invaluable.