I have been widowed twice, both times I was advised by my therapist, to wait at least a year before beginning a new relationship. I have to say, that was the best advice I had ever received.
During the first year, a person is grieving and not really able to make rational decisions, due to loneliness they may jump into the first relationship that comes along without really seeing things as they are.
For me, at the end of the first year, I was able to look back on a few things and Thank, someone or something (?) that I had waited.... otherwise it would have been a disaster.
This applies not only to relationships, but also financial decisions, include selling or buying a new home... alot of regrets can be made during that time period.
Cas