The definition of love can be pretty ambiguous, love of ones family, love of a significant other ect ect. I would bet the consensus on this board would be that 'loving' life as a process is both practical and effficient, this of course would include death and destruction. It's tough to think holisticallly, I struggle with it at times, but a love for this natural world, and life as we know is necessary as I see it.
It's possible to both love one person, and love a tribe and customs. Just because some of these things are not prominent in modern western society, it doesn't really make any sense to throw out love completely. I don't understand your 1984esque rant.
To answer the OP - It's necessary to love life in order to be contructively effective in a positive way on this planet. Not to sound overly Christian, which in some cases isn't bad, but we are imperfect creatures that tend to be selfish and shitty, there is no perfect relationship, everyone gives and takes something. I can't say to much more on the relationship portion of your question as it pertains to women, as I don't think I've ever actually loved one as deeply as I could. We are wired to be pack forming animals, so of course genes play a part, in fact in most cases they demand it in a certain sense. Upbringing plays a small part, although I would think most would agree that once you come of age, if you are intelligent, you leave behind the worthless parts of your upbringing (as best you can).