Depression in the 3rdtrimester

So I haven't been right mentally for about 2-3weeks now. I'm wanting to cry at the drop of a hat and I want to distance myself from family and friends. I know all the signs since I have battled depression before. 5 years later I thought I won. However now I sit in bed dehydrated from lack of consuming food and fluids, nauseated, sleepy and in a constant daze. 4 days prior to where I sit now I started having this ear pain and headache. All of which I thought was the start of a sinus infection. I go to the doctor and she tells me its stress and TMJ. TMJ is a disorder of the jaw joint. The friction from being tense and grinding teeth can cause the appearance of an ear infection due to where the pain lies. Well, I didnt think stress had anything to do with it because life is fine. I have learned in my battle with depression stress is what you make of it. Subconsciously or not stress is there and triggers just about any underlying feelings. Well I pushed it off for 2 days before I finally broke down. I cried uncontrollably for hours. I have nothing wrong with me why am I crying. My family is healthy, this pregnancy is healthy, I have the perfect life right now what is the deal? All the fake smiles, upbeat attitude, and sarcastic jokes were all a cover for what really is going on. Burying the problems that came my way. If it wasn't my monkey it wasn't my circus and I didnt deal with it. Why? It does nothing but cause stress. Subconsciously it was causing my stress. I acted like it wasn't bothering me but deep down while I slept and was shaken from my sleep by a shrilling nightmare it erupted. Like I said now after I sit in the bedroom, in the dark room just like my mind I wonder how did I get back here after 5 years. If remission for depression is a thing I'm proud it stayed at bay for 5 years. Now with a 2nd child on the way and a beautiful family I want to love my head so full of unwavering and unsteady thoughts. I can't stay strong for this little one in my womb. I can't be joyous because I don't know how much longer I can go on working 40+ hrs in a toxic environment, and driving 50 mins 3 times a week. But life is great. My unborn child is healthy. My husband is healthy, my 4 year old is healthy and excited about life. My extended family is happy and joyous plus 100% supportive for the new life coming. Why now coming towards the end of this beautiful pregnancy I can't handle life?