2nd July!! That's my dd4's birthday. She was born 2nd July 2002, at home with no dr and no drugs. H had gone to DIY store and I had her on living room floor while he was out, LOL. Really GREAT experience
My H was born 9th October 1974 so he's a bit younger than your S 30.
You could tell your DD 15 you miss her - love might come across a bit suffocating if you don't normally say that, and as you said, I think actions speak louder than words so just demonstrate you love her by doing the things you mentioned.
It's okay to be sad, but my point is, you mustn't be sad in front of relatives. Save your sad moments for the MC on or your own.
Think of it this way, no one wants to come back to someone who is whining etc. If you're miserable, what has she to come back to? You have to act fun and sexy and confident like you were when you married her - even if at this stage you feel you have to force it, it's important to behave like this. Focus on your end goal and that will help you stay in control of your emotions.
