Can't deal with my brother who has Aspergers Help

I cant' deal with my brother who has Aspergers.  Help.  Yesterday we were out for dinner with my brother Don and his friend Blair.  He kept going on and on about all the abuse he suffered from our mother, other people and his ex wife.  I can't deal with it anymore.  I am at the point that I don't want him coming over to my place anymore.  I recently lost my husband.  I am grieving for my own loss which is making me impatient with my brother Don.  I think I am losing it and can't handle him anymore.  I feel like a big meanie but I can't handle Don and still cope with the sudden loss of my husband.  I am a grieving widow and can't deal with my own life let alone Don with his Asperger's Sydrome.  Anyone know how to deal with this particular situation or can give me any advice on the subject matter.  I am at my wits end.