C.M.
Well relationships are hard and i have found the hardest of relationships are those that contain those with children from previous relationships.My boyfriend(of almost five years) and I have been raising his daughter for the past four years and my son for the past four years. so I know how difficult it is and it has to be worse for you because of their age. I would talk to your boyfriend and have him sit down and make a schedule with his and then your ex. Tell him you need him to do this, because its not fair to you or those children to have such a mest up schedule all the time. I have noticed with my ex's daughter she comes first, which is how it should be.. but i do have a problem with it sometimes.. I guess you could look at like this, if she is leaving them with you at least its with you and not someone you don't know. i think i would talk to someone about custody. but so you know, its a struggle being a step parent. i hope this helps and if you want to talk i'm here.