Hi there welcome to PTalk.com!
How do they work? You simply use them as if they are colognes or perfumes 
It’s that simple.
You might want to take a read at;
https://pheromonetalk.com/t/an-introduction-to-mones-names-size-strength-use-effects-length-of/43003
https://pheromonetalk.com/t/how-do-i-qualify-for-a-25-gift-certificate/19934
In regards tot he relationship, both of you have to be honest with yourself. Do you really still care for each other enough to get back together. And you need to find out the mai reason as to why both of you left each other. Find the root of the problem instead of trimming off the weeds.
Sexually, for mones, you might want to try out some TUTH for him and some IS/b for yourself.
Mones can only do so much, in your case, it’s more of a matter of solving the issues rather than putting all the work towards mones. TBH, they aren’t the magic pill.
You are.
Cheers!