I hated Tom for what he did!
I loved them since the beginning. If Liz could forgive him though, I felt like I should too.
Not forget all he did, but trust and believe that he has changed. He didn't intend on falling in love, but it happened. You can't help who you fall in love with! I believe Liz has always loved him, from the first moment they met. Tom fell in love later on as they got to know each other better. I'd like to think though Tom had a little crush on her since the beginning but duty over everything so he tried to fight it.
And I think he has proved now he'll do whatever it takes to protect Liz. Even if those ways are ugly and cruel and mean. Tom isn't perfect and the choices he makes are far from it.