Jaye Richards-Hill, an equal rights marriage campaigner, told Paisley Sheriff Court yesterday she was left feeling "utterly degraded and shocked" by the comments, which the prosecution claims were posted by David Shuttleton.
She told Mr Shuttleston's trial they were put up on the social networking site after a message was posted by former First Minister Jack McConnell in favour of the forthcoming legislation.
She contacted police because she felt her professional and private reputation could be seriously tarnished.
Mr Shuttleston, of Barrhead, East Renfrewshire, denies behaving in a threatening or abusive manner likely to cause fear and alarm to others between in June and July last year by repeatedly posting messages which were grossly offensive or homophobic on the Twitter and Facebook.
He was allegedly disagreeing with Lord McConnell's stance and that led to several inter-actions with others.
She became alarmed when the accused started to use hashtags such as "danger to children" in relation to subjects about Equal Marriage which she had an interest in.
The trial was adjourned.