Recently a friend told me that it is not proper to eat out in restaurants when one is an Aveil. I have been searching for a source that prohibits this. Does anyone know of a source prohibiting eating in a restaurant when one is an Aveil?
I couldn't locate any source that specifically addresses eating in a restaurant. But I am excerpting some items from this article:
A mourner is defined in halacha as someone mourning during the 12-month mourning period for parents or the 30-day mourning period for the other five relatives (spouse, brother, sister, son, daughter). After 30 days, one is no longer a mourner for anyone but one's parents.
Then, the site explains the problem of eating meals outside:
A mourner may not attend a public meal for any purpose. For example, if the mourner attends a lecture or Torah class at which food is being served, he or she may not eat the food. This only applies to sit-down meals; snacking is permitted.
OK, so the question is if going to a restaurant is considered a "public meal". When I look at the examples listed further on that web page, he lists weddings, bar mitzvah, Torah lectures. The commonality is that this is a sit-down meal designated for a group of people who are considered a unit eating the same (mostly) food.
A restaurant doesn't seem to fit that definition. They are a business and people order from a menu and eat at different times. However, an office party catered by the same restaurant sounds like it would fit the above definition of a "public meal". That's my own analysis.
What does seem clearer from the above quote is that it seems restricted to a sit-down meal. If you go to Starbucks and drink a coffee at the table there, I don't think that's considered a "meal".