When the electron is inside the proton orbit (right side of the periodic table) the proton is left exposed. They repel other similarly exposed protons but can acquire another electron and so gain a net negative charge.
When the electron is outside of the proton orbit (high Atomic number elements), it is itself exposed and can be shared with similar proton orbit that has yet to acquire (or has lost) an electron. A electron rolling outside of the proton orbit, participate in ionic bonding.
Note that this occurs after the proton orbit has been paired with another proton orbit.
When an element with electrons rolling outside its outer proton orbits lost an electron it becomes positively charged and becomes a cation.
In this explanation, it is not necessary that an anion or a cation form first for ionic bonding. But it is possible that in an aqueous solution, the ionic compound separates into ions that are stabilized by the polarity of water.
Between inside of the proton orbit and outside of it, an electron is in a helical path partly inside and partly outside of the proton orbit around the nucleus.
This however presents a problem, if these are the inert gases at the end of the row in the periodic table, why does this type of orbit occurs after the electron has moved inside? It is likely that as we move across the row of the periodic table more proton orbits in the outer shell reduces the separation, \(d\) between the paired orbits. This increases the time-average positive charge along the orbit and pulls the electron partially outwards again. What is odd is that this happens consistently when the outer shell has four paired orbit of eight members in total.
The nature of the electron's helical orbit, part of the time inside a positive charge's orbit and part of the time outside of the positive charge's orbit, prevents the negative particle from being shared. If two elements were to share an electron, the sharing positive charges are exposed when the electron is inside either of the two proton orbit pairs. The exposed positive particles will repel and break the bond. The paired orbits cannot be paired into four without first removing the orbiting electrons which would require high energy. No electron sharing and no orbits pairing means that the element does not readily part take in chemical reactions; it is inert.
Just rolling along...
