You love hundreds of people in your life, in different ways. Some no less intense than others for being different. But it sounds like that question was more about capital-L, romantic love. The sort hollywood would have us believe is "one and only", soul matey kind of stuff.
Maybe it depends on the person/people?
I know that for me, when I've been in love with someone I've never developed those feelings for a second person. Don't get me wrong, I'll get silly crushes. Even big, pulse racing crushes. But I've always known that's exactly what they were.
But that's me. It's how _I_ work, or...more to the point...how I've worked so far. Life may just have held that curve ball back until it's good and ready to get me.
But if that curve ever comes, well....I'd do a lot of thinking. Cause I have to say, my first instinct would be that it was a sign that something was missing in my first love that I was seeking in my second. And if that route came up empty, and if I decided it really was just a case of Fate sending me two perfect people at once....well, after I was done being pissed off about the unfairness of it I'd have a good long think about what I was going to do about it. Because, knowing me, I'd be worried about one of them getting hurt because I was careless. It's not a situation I'd want to be in, frankly. And if I couldn't find a harmless way to fit them both into my life, I'd probably walk away from one. I'm, well, I can be a practical little bitch when I feel like I need to be. Not my most attractive quality, I know.
But to answer your second question (finally)....no. Simply no. I think two true Loves can't possibly diminish each other. I don't think they'd even speak badly of me. Just make my life complicated and raise possibilities for pain.
Which is more than my 2 cents. Sorry, your question got me thinking...and that's always a dangerous thing

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