Seasonal depression & people not understanding..

On the phone with my mother in law, explaining that A. I'm exhausted from my baby not sleeping well the past few nights, and B. Seasonal depression is also kicking in a bit. And that I'm trying to work through it. Mind you, it doesn't get to a point of me not being able to get shit done..it's not like I mope on the couch all day or take anything out on anyone. And I say to her "well I'm working on it, I just don't want to take medicine for it honestly..I know I can get through it without it, it will just take the right motivation." And she starts insisting I should take it...after I just said I didn't want to. I get that she has no idea what this feeling is like, but I just feel it's inconsiderate to insist on something I JUST said I don't want. She also makes me feel really weird that I even go through this in the first place, like I'm "broken" and her son married the wrong girl. It's just the feeling I get and it's in her reactions/responses when I talk about it.