I bought a Model 3. A year later, her car was an X. As others have said, having a Tesla in the garage goes a long way toward putting another Tesla in the garage.
For my wife, it was a combo of things: the driving experience, environmental concerns (no more gasoline at our home), safety safety safety, never needing to stop for gas again...
We settled on the X as we wanted a 7-seat vehicle for times when we have extended family in town, carpooling, and road trips with others.
Have you considered a Y? If it's just your family of 4, you might be surprised at how well a Y works out. We've taken multiple long road trips in our 3 and it's amazing what it fits. I have no doubt that with 4 occupants the Y would fit anything you could possibly bring. The X is now only really needed for carrying more than 4 people plus a bunch of stuff. I mention this as cost seems to be a sticking point, and the Y could save you $25k vs a new X.
If you do go for an X, I generally recommend a new X vs used as the price has come down considerably while the range and reliability have both gone up considerably.
Whatever you decide, welcome. It's hard to describe how great it is to drive these cars