Ian's Death

Im confused about how ian died. Red coat pushed him off thr ledge in the church to save spencer. In the clip we saw of Ian after it looks like the ropes has strangled/ hung him. He looks dead. How the hell does he survive that fall???

The liars later find him the in barn thing with a gunshot in his head and a suicide note. Doesn't emily figure out that the suicide note is written using A messages?

How does he acually die? Cause I thought he was killed by the fall off the bell tower and then Mona or one of her minions moved his body before police could get there. And she staged his body to make it look like he committed suicide. We know she was texting Melissa from Ian's phone to lead her on.

So what acually killed him? I thought it was implied that ian had died in the church. Also why wouldn't he go home? He had a kid on the way? He easily could have scared spencer and the liars into not telling anyone. They never tell anyone about any thing anyway. And why was mona texting mellisa or was it acually ian?

Side note if ian didnt die from the fall, how does he survive that but Shana died from falling off a stage? Make it make sense. Her death pissed me off to be honest.