#!/usr/bin/perl
my $line;
while (my $line = <DATA>){
$line =~ s/<span><p>(.*)/defined ($1) ? "<" : '</p><p>'/eg;
print $line;
}
__DATA__
<span><p>This affected me deeply because < I was being treated for dep
+ression then. < felt she was replacing me as mother and grandmother.
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This is just printing '<'. But the output needed is

<span><p>This affected me deeply because </p><p> I was being treated f
+or depression then. </p><p> felt she was replacing me as mother and g
+randmother.
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