I would have to echo what has been said previously - your hobby is your hobby and you do it primarily for you. If others find it interesting that's fine but, given all of the things that are out there for someone to turn into a hobby, it really shouldn't come as a surprise when someone close to you decides to chase other things.
In my family I was the only one interested in trains and with one exception in one neighborhood where I lived (we moved a lot) I was the only kid I knew who had any interest. The interest has never faded and I doubt it ever will.
As for my son - no interest whatsoever. What I have done is make sure I have an inventory of what I have so that when the time comes he will know how to dispose of the trains and get some money from them. This doesn't bother me - I have had endless hours of fun with the trains and everyone of them brings back a memory of a time, a place, a person, or an event. However, once I'm gone they will revert to what they really are - a semi-random collection of items of no particular importance.
