It's tough, but it's not impossible. A relationship re-try definitely has some built in hardships to it, but it's not entirely impossible. The things I would watch out for are hidden anger or resentment, the same recurring issues, inability to forgive the past, things along those lines. But if two people are willing to give it the best chance possible, it can work. I really think that if you're looking to get back into a relationship with an ex, then you should get couples counseling. The fact is, if the relationship failed the first time, you might need a professional or an objective opinion to help you mend the relationship. If you could have worked it out on your own, then you would have, right? So I think in a situation like that couples counseling would give the couple the best chance at survival. It's all in how much you are willing to put into it and how much you are willing to risk. It's risking a lot, going into it knowing that there's a good chance it might not work out. It's up to the two of you to decide if it's worth the risk, time, effort, and energy. But if it's what the two of you want, then counseling can assist communication, deal with past and present issues, forgive things that have happened in the past, and just work things out in general. You're right, we are all human, and we do make mistakes, but whether or not that mistake is something the two of you can get past depends on the mistake and on the two of you. I hope that helps.
Army Wife. Psychologist. Nurse.