My ds, 18, was on escitalopram 20mg for 4 months and is now switching to sertraline.
He has intrusive thoughts ocd which started when he was 15 and became progressively unmanageable - to the point where he was self harming, having huge panic attacks, and lost so much weight he was referred to an ED unit.
Since starting AD he is a now a normal weight, sleeps for longer (he used to be up and about by 6.30am even in the holidays) whistles around the house and we can have a laugh with him.
He is nowhere near 'cured' and still has bad days/the intrusive thoughts are still there but less intense so compared with how he was, it's so much more manageable and life for all of us is more pleasant.
I hate him being on them, resisted it for ages and dread him maybe having the struggle to come off then one day, but he really had no other option as he had already had 4 lots of CBT therapy (which certainly helped and gave him strategies) but wasn't enough.
I don't think AD can make you happy, that's not their aim; they are there to enable you to function and engage with life in a more positive way which in turn allows others to support you and be positive around you - and therefore life becomes better. That's our experience anyway.