OBSESSIVE和OBSESSIONAL有什么区别呢请举例说明下

OBSESSIVE迷恋的，萦绕于心的; 有执著想法的 2. 固执 偏执的
OBSESSIONAl摆脱不了的，强迫的

She's obsessive about punctuality.
她对守时十分固执。
An obsessive need to win.
急迫的想赢的欲望
Obsessive preoccupation with the self.
利已狂对自我的过度专注
An exaggerated or obsessive concern or fear.
夸大的或过激的担心或恐惧

He is obsessional about tidiness.
他过分爱乾净。
the obsessional character of his response; obsessive gambling.
他的回答的着迷的特征；着迷于赌博。

为什么强迫症英文obesessive-compulsive disorder前俩单词一个意思？

obsessive和compulsive一样的都是强迫的意思, 但
obsessive 强迫主动 means think about sth too much
compulsive 强迫服从 means doing sth persistently and repetitively without it necessarily leading to an actual reward or pleasure.
简单点，一个乱想 一个瞎做。
So this way, a man with OCD will find his obsessions uncontrollable and the compulsions impossible to resist.

Hope you get it.