Nothing is as simple as love or hate, trust or mistrust. Trust people when it's a matter of their well-being. If they tell you they're in pain, treat that. If they say, "Honey, I know I smell like hookers and I'm gone all day every Friday until the next Sunday, but I am not cheating," use your brain. Trust is situational, rather than individual. As far as loving everyone, not realistic, but we can treat everyone with love. Ostentatious fawning? No. Treat them with respect no matter if they're adulterers, drug addicts, murderers, homeless? Yes. It's not appropriate to frequently hate and pass judgment.
To me the quote is not a literal thing. Love all, trust a few, do wrong to none. William Shakespeare Love all, for me is to accept all for who they are all regardless of who they are. Trust a few, for me is that those who will become part of my inner circle of people are those that I do trust. Do wrong to none, for me is that no matter what I feel about anyone, I do not have the right to do anything that is hurtful or deceitful. I actually do try to live life very much as what those things mean to me. Sometimes I do not totally succeed but I do make an effort to.