It's not a matter of getting people to like you, it's a matter of preventing people from getting hurt. Lovesickness and heartache are, in my experience, among the worst, most devastating pains the world can offer.
You can follow the ethical principle of always telling the truth, you can also follow the principle of telling white lies whenever that will make the other person feel better.
If you are consistent and the other person can expect you to follow your principles they won't ask you for opinion if the truth will hurt them and you have the policy to always tell the truth.
If you don't have principles and sometimes tell the truth and sometimes tell white lies, it's however much harder for the other person to interact with you to avoid getting hurt.
When driving an...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.