salamun alaykum all,
When it comes to "love", i remember 9:24 which gives me the message that the love i feel towards "anything worldly" (including families, wives, sons, daughters, friends or any kind of property etc.) has some boundaries that must be upheld no matter what.
Say: If it be that your fathers, your sons, your brothers, your mates, or your kindred; the wealth that ye have gained; the commerce in which ye fear a decline: or the dwellings in which ye delight - are dearer to you than Allah, or His Messenger, or the striving in His cause;- then wait until Allah brings about His decision: and Allah guides not the rebellious.
Perhaps, this ayah was revealed about war (qital) or something specific, but i understand it as a general principle in life. Just like you said Seraphine, it keeps you away from "unnecessary heartache". Keeping in mind that nothing matters more than Allah (swt) and His commandments (His messenger, His cause...) He is the one who cures your heart when it breaks.
Of course we sometimes fail to live by these principles but where's the harm in trying our best to do so ?
Take care.