Should I marry my ex or go for a fresh wine?

Hello AVL,I have been following your post quite a long time and i think is best to share my experience and ask for advice as i welcome insults and real advises. 
I had a lady i was dating some few years back,i so much love her but she kepting hurting me,after dating for five years i decided to date another lady for the fear of her breaking up with me eventually,she later knew i now keep another date and we both talk it over,i secured a job in the city after three months of dating this new lady.After settling down i asked the former lady to moved in with me cause of my fear of loosing her to another guy in my absence,the other lady knew about this and we eventually broke up but she kept hurting me,after a year i have to advance my studies which made me to leave her anyhow but when i returned for break i realised she had been dating a new guy ,i was badly hurt that i had to return the following day.After my programme i tried to get the other lady but she had gone back to her former boyfriend and they stayed together,i appologised my attitude to her and she let go the past.
After a year my ex got married and i continued with this other lady which i eventually married and we had a child but most of the times we get misunderstanding and she keep telling me that she can't love me as before again now we've broke up and my ex also had broke up with her marriage.
She is now asking me to take her back that she had realised her mistakes moreover her husband is begging her to come back but she insisted that is me she want that she is not returning into that marriage,we both have a child and am confuse whether to forgive her and marry her or go for a new person
Pls i need your sincere advice

Dear sender, 
Marriage is not a draft game where you can jump and move at will. 
You didn't state exactly what these misunderstandings was which made you to break up with your wife but I feel that both of you carried the pains of the past into your marriage and both of you kept grudges of your weaknesses in the marriage to each other which made you feel that your ex would make a better wife than her. 
The plain truth is, even if you end up with her you would break up with her because your emotions are not stable and focused for a fulfilling Marital life. 
Do not rush to marry your ex I would suggest, rather return back to your wife and mend the fence with her. 
Remember that your child will be affected greatly by the decision you make today. 
Settle down and make your marriage work. All the pains of the past should be gone and you shouldn't be wishing and thinking the other lady was the one that you married. 
She is married and she has a child also with her husband making her vulnerable to him. 
Forget about getting a new partner, they may not be what you thought but a lady with weaknesses who craves for the love, support, appreciation and care of her husband. 
Return home and return to God who is the author and finisher of our faith. Surrender to Him and he will perfect all that concerns you and your family.