CANCER MAN ? OMG - what a struggle!

Guys,

I am dealing with a lovely guy, so caring, funny man, very easy to fall for...

But God, what on earth is happening at times with him is worse than woman on her period! I don't quite understand his moodiness, he shuts himself and there is nothing I can do.

. There are some obstacles between us and I am being very careful on who to trust, so does he, I reckon. But all of a sudden he turned cold, I know he pays attention to me when he thinks I am not looking but once I have approached him, purposely starts ignoring me. Asked him what is going on, if he's ok, and he either lies and says all is good or does not respond at all.

He's a lovely person and I want to take easy, you think it is a good thing to have a good chat with him, tell him what I feel or how I feel? He can be sweet one sec and then harsh the second after. NEVER opens up, and it is hard to let him know he can trust me. He carries a lot of worries with him lately, sometimes I just wanna hug him and be there for him. Although when I already know he's in crabby mood frankly, I am scared of him that moment LOL

Any idea how to approach him and win him over?

Thanks!