DATING A WIDOW

For the past 7 months ive been dating a girl who recently became a widow....She was married 34 years and although the beginning of her marriage was rough it ended up working out very well between them

My problem is that every once in a while she gets terribly depressed and grieves...when that happens she falls off the face of the earth....as she needs time to be alone

When that happens i begin to think she isnt happy enough with me...it seems to me that at such moments she is realizing how much better for her he was and this makes me feel 2nd

I dont cope well in this situation....i get unhinged

Does anyone have experience with this sort of a relationship...are there any men or woman who can give me advise