Sexual frustration

Hi,
I just found this forum and I think this is right place to discuss being complete stranger and without being judged.And I hope this is an active forum.

I from UK,married but lonely . I've high sex drive but my wife isn't interested in sex.I discussed with her many time but nothing improved.Most of the time I have to masturbate and then I feel guilty.
I don't have friends too and I feel lonely most of the time.When I'm too bored I try to for phone sex with strangers but there are lot of scamers out there.And I don't want to cheat her by having a gf.
I feel like I'm stuck.