I am 39 years old divorcee lady with two kids 11 years son and 10 years girl respectively. Recently I came across with a person who cannot marry me due to his family situation but I would like to have long term relationship with him as well as he can continue to stay with me. He loves my kids as well as kids accepted him as a father figure. Now my question is there any difficulty to absorb him like step father by them and how would it effect on them psychologically?

With all concern to the psychological effect on your kids you should be careful in introducing a new father figure in their life. Also be aware of the fact that when this man will walk out (if he does) of their life it may be more painful foe them. Also with their growing age there might be many more issues you will be address too.