first and foremost salt and iron my friend, a demons worst enemy, also, since you know the demons that are after you, I suggest finding their sigil, if they bother you, burn the sigil, that should send them back to whatever it came from. if your up to it you can draw the triangle of solomon, call upon them and then banish theme just as you feel their presence. I find that to be the best solution but not everyone is willing to actually summon the thing that indangers them.
this is the exact same problem I have but it is a very powerful demon. and it is destroying my life in all aspects! my relationship with my beloved is being ravaged and ive been arrested for a huge misunderstanding! someone please help!
You asked about the Queen and King cards. (you said hearts but I'm assuming you mean cups?) The King and Queen of cups if they represent you and your boyfriend, are very loving cards. They show love and kindness. You probably have a very loving bond with each other.
The other posts give some great protection advice :)
Salt typically. And not all demons are evil or have evil intentions. Demons are best described as impulsive. If you have a calm approach about it you can simply as the demon to leave you alone. If that doesn't work and it becomes aggressive, figure out what it wants and then decide to... Contact an exorcist, get a cleansing, ignore it, befriend it, or subjigate it.
However it's also possible that the reading you had done was complete bull, and your actually fine.