How can there be both molecular and non-molecular solids?

Non-molecular solids are of the type of metallic and ionic solids. They are held together by the strong electrostatic interactions of polar particles like ions and electrons. For example in metals the strong interaction comes from the attraction between a regular arrangement of cations (positive) and a sea of delocalised electrons. Whereas in ionic solids (like salt NaCl) the attraction comes from the electrostatic interactions between cations (positive) and anions (negative).Then how can you have solids of things that are molecular, when molecules are often too small to even really comprehend or see under an optical microscope? The way that molecules can form solids is because they create intermolecular forces between one another, there are a number of different types of intermolecular force which are again based on the positive and negative sub-atomic particles that make them up i.e. electrons and protons. Different atoms that make up molecules have a different affinity (desire to look after) for electrons (electronegativity) this leads to a build up or lack of charge on different atoms, creating similar interactions to the ones in the non-molecular solids mentioned above, as such under certain conditions this allows for molecular solids, like ice...(Question from my 20 year old sister who struggled with this concept)