HELP! CUPID HAS SHOT ME A COMPLICATED ARROW

I got this letter from an ardent reader of my blog in a really complicated situation seeking an advice. Well, I in-boxed her my thoughts with regards her current dilemma and she asked I share her story for directions and advice.
Check out her letter below.

Dear Chidinma,

I am an ardent reader of your blog and I must commend your efforts with regards your posts and updates, though you hardly discuss relationship issues.
It will be really nice if a segment on relationships trials , triumphs etc can be covered on your blog.
I have had this burden in my heart for quite some time now, but have not discussed it with anyone including my close friends, because I do not want to be judged.

Without wasting so much time, my name is Amara. I am currently in my late 20's, and unmarried.
Why I have pondered as to why I am yet unmarried, I am grateful I have a job that provides me  a source of income and sustains me.
Well, in this era of social media, I cannot help but confess that I get tortured with pictures of my peers either married, pregnant or with their children posted on Facebook etc.
Trust me, as much as I try not to get bothered believing mine would come someday, I cannot help but be anxious . Thoughts like when, how long , how much more time etc engulfs my mind constantly.
Not like I haven't had proposals in the past, but the men were either not what I truly wanted or something goes wrong and we get to part ways.

Recently , I met a man in his 40's. He appears to be everything I ever wanted, and I have a pressing feeling that he could be the soul-mate I have been waiting for. 
The challenge however is that he is a married man, and we hit it off right from the first time we met.
The feeling is completely mutual and he often tells me he wishes he met me long ago since his current marriage was an arranged one, and I in-turn have no doubts that I would have said  yes if we met earlier and  he proposed.
He is everything a woman wants, kind, compassionate, generous,calm, hardworking , God fearing etc.
Now,  this is totally not about money, because if I needed a married man for material benefits, he wouldn't come into the picture.
We haven't been in anyway intimate because I initially thought he was one of the numerous randy men seeking mistresses, but to my surprise, he dosen't  even stress sex.

He often makes comments as to us getting married since anything was indeed possible, but I have made it clear to him that I can never be a second wife let alone marry a divorcee incase he strategizes starting trouble or breaking up with his first wife because of me.
To top it all, I emphatically told him my parents would never give their blessings , since they'l picture me as an intruder .
Despite all I have done to turn him off, he keeps pushing and I am afraid to say I have fallen for him really hard.
I really do not know what to do. I don't want to be a mistress, second wife  or a homewrecker.
Is it possible for ones soul-mate to get married to another woman considering in this case that his marriage was arranged?
What do I do, please I need your advice.

Yours truly , 
Amara