18 Months since dad died

This week it's been 18 months since my dad died.  My mom came over yesterday for the yearly taming of my front yard (there's a couple of bushes that we cut down every year to the ground and they grow back bigger the next year).  We were talking about how my dad would have been helping us if he was there, carrying the brush to the compost pile in the back yard.  And even how my yard would never ever look neglected or overgrown if my grandpa (her father) was alive--he died a few weeks after my high school graduation, in 1987.   (My mom lost her dad when she was 42 and I didn't even make it to 40 before mine died.)
My mom said that she never thought she would miss my father so much.  The last few years, especially the last few months, he was mostly a burden.  I know that sounds awful....unless you're a caretaker and then you understand.  But now that the violent and confused Bob is gone, we can remember the real Bob, and miss him terribly.
I've been sad all week.  One of my birds died 3 weeks ago, unexpectedly.  Doing all the dead pet things--the crying drive to the vet, going back to pick up the ashes--made me miss my black cat Zen again--and realize that on August 1 it will be 3 years since he left me.  I still feel awful that I didn't say goodbye--I didn't know he was going to die before I ever saw him again--did he think I abandoned him and just give up in less than a day?
I'm reading a book about the conquest of Mexico--a topic that boils my blood.  The Mesoamericans believed in cyclical time.  Time loops around and we have a chance to do it all again:
"Another time it will be like this, another time things will be the same, some time, some place.  What happened a long time ago, and which no longer happens, will be again, it will be done again as it was in far-off times: those who now live, will live again, they will live again."