The difference between social isolation and loneliness
Social isolation is the act of being separated from other people. This is often a choice for people who live alone. It can also be an acute, temporary, situation, such as the required isolation during the COVID-19 crisis.
Social isolation is the objective physical separation from other people, while loneliness is the subjective distressed feeling of feeling or
being alone or separated. Many people who chose to be isolated are content with their situation. When social isolation is not chosen, it can lead to loneliness. It's also possible to feel lonely while among other people, and you can be alone yet not feel lonely.
The two are not the same but it is important to recognize loneliness when it occurs, and talk with someone about your feelings - you are not alone and there are resources to help.