I found out about the Law of Attraction when I was desperate to get different people back into my life at various points. 
I'll be honest, I never got back in contact with the person I wanted to bring back into my life. I wound up meeting someone else I felt much better being with and it didn't feel like work with him. We've been together for 2 years and are very happy. I have manifested exes back into my life, but old habits die hard, and they left again. 

When a relationship ends, you tend to overlook the aspects of the person and the relationships in general that weren't great and put them on a pedestal. It hurts, right? Deal with the hurt first. There is no hurry, the longer you let it get to you, the more you'll get back.

You also need to be clear on what it is that you want from a relationship, a lot of people set their minds on just getting a text. Don't you want more than a text? Do you want someone who'll sit with you, rather than going to a party and just watching whatever on Netflix? 

This is what messed me up the most in regards to manifesting, impatience. I'd force myself through whatever routine I'd set myself, I'd hear my phone make a noise, leap for it, then wind up irate that it wasn't the person I wanted to hear from at that stage. That behaviour was alienating. 

I could do a more in-depth post in the future if anyone is interested.
In these situations, we tend to set ourselves on fire to keep another person warm. 
What I've mentioned where good jump-off points for me to realise that I had to do some self-reflecting.