I find Shula's character a recognisable one Nellie. She wants to be 'good'; it has always been an interesting contrast to her twin who did not seem to care in the least about being 'good'.
The issue with anyone who has this sort of character is that their 'good' is not always other people's. The issues she had with Alan marrying Usha where very much of that type. She seems to believe in her religion. Many people who are, one could say almost fundamentally religious have opinions others, who have not such a strong belief or have not belief at all, cannot understand. She could not understand why a leader of her religion did not agree. Her views are not subtle; they are very clear cut.
She certainly did the 'wrong' thing when she had the affair but her sort of character would have, I believe, beaten herself up a lot more than you, were you to know her, would have done. Along the way she has not learnt, or perhaps not accepted, that people cannot always live up to their own standard of 'good'. She is still very upset about how she behaved re the hunt sab and is not the type of character who will ever find it easy to forgive herself.
When it comes to her being 'irritating' I would recommend the story of The Scorpion and the Frog - it is her 'nature' and she can no more go against that than you or I can go against ours. It is kinder, imo, and more useful, to try and understand her behaviour. One of the great things about drama as with books, is that we do learn about things outside our everyday sphere of knowledge.
My argument is not with Shula's character; it has become very well drawn over the years. It is with the way the SWs are manipulating it. Maybe they will have a reason which is totally in keeping but it doesn't feel like that at the moment.
(I expect someone to shout at me for taking this too seriously now - but that is my nature
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