its same happening in my life.
if you cant trust him just leave him. sure he will feels for you. because i have questioned him lot by being with him.i watched him in 24/7. he get depressed about me. now he is not tallking with any girls even to me. i am least important to him now. i am feeling guilty now. may be he was cheating at particular age but he loves me only still he needs me. there is no more love occupied between us.

all mens are same in this world. they will cheat lovers by talking with some girls but they wont accept frankly. i am not saying that talking to all girls doesn't mean that they are having affairs. may be they are just friend. he may be hiding because you will suspecting him every time. just express your love to him. try to make him feel guilty by cheating you and talking with other girls. don't questioning him further. try to be calm and please handle him in polite manner.. its all because of possessiveness or insecurities.
Showing your love and trusting him can regain your love. just bless the god who gave you a good person who needed you last 10 years.