Depressed

I'm feeling depressed today - that's only a summary !
Well, it started even before I got out of the bed. And when I think now, that's the only bad thing since then. yet, I'm very much hurt. Unfortunately, an hour of gymming and half an hour of cooking haven't wiped out the bad feeling.I'm in office, but my thoughts are elsewhere. I'm extrapolating my today's scenario on a future plan and feeling insecure! My question or worry is: Who will take care of me when I am old and sick?
I donot have kids and even if I get one, it is not correct to be dependent on them. My husband had already expressed his inability to fend me when old and said that the house I'm constructing should take care of my financial needs in future. I'm paying the EMIs and gonna do it for another 20 years- how nice! He helped find the property and his duty or support ended there, in his opinion. Neither he is bad nor is he right!
I'm wondering if that would be enough or if that would be my only need ?
Is this what happens when both the partners donot love each other? I don't know what is love!
There are so many uncertainities in this universe around me and still I worry about what happened to me which leads to what would happen to me!
Irony, isn't it?
Or, is this life? Am I over engineering my feelings or these are natural emotions which a normal person undergoes?
Better I forget all these things. But how?