If someone close to you thinks they may be a victim of stalking, or is being stalked, one of the most important things you can do for them is to validate their feelings by listening to what they have to say.
Avoid shrugging it off or using phrases such as “Well aren’t you flattered?” or “I’m sure it’s only harmless”. Phrases such as “I’m sorry that you are experiencing this” or “I understand that this is frightening for you”, are much more supportive. People aren’t always asking for a solution, sometimes they just need to be heard.

Avoid victim blaming
Statements such as “I bet you were too nice to them” or asking questions such as “What did you do to them that caused them to become that obsessed with you?” can often evoke feelings of shame in victims. It can make them feel as if they have done something wrong. No one should have to endure being stalked for any reason. 
Offer help where possible
If a loved one is being stalked, simple things such as going to the shop or going for a walk becomes significantly daunting for them. If it is in your capacity and safe to do so, accompany them on errands or journeys to/from work.

In case of emergency
If you are concerned for the safety of your loved one, offering to assisting them in contacting a Protective Services Unit or accompanying them to report a crime to the Gardaí can help make the situation less daunting for them.
Help and support services