Depuis clarification

Question

Depuis has gotten confusing in this forum likely due to one comment stating emphatically that Depuis is used for a duration that starts and ends in the past. The lesson says no such thing, yet the incorrect comments show no clarification, and we are left to wonder. If Depuis cannot be used for a duration that starts and ends in the past, then something should be mentioned in the lesson, or, better, corrections should be added in response to the incorrect forum comments. Otherwise, it is confusing. Thank you much.

Answer

I think that... Depuis means since, or ever since. An ongoing action / event, state etc... which began at a specified moment / time/ event. J'ai gagné du poids depuis que j'ai eu mes enfants. I've gained weight since having children.