Hi,

my boyfriend has quite a serious case of depression and is on a waiting list for a psychiatrist at the moment. I met him six months ago on holiday and didn't realise until i had feelings for him that he was depressed as i don't think he quite new at the time why he was so low. he struggles to tell me the main things that he thinks of that cause him pain but has told me that a major part is due to his ex girlfriend but also his work, he's a police officer. He says he was depressed during his relationship with her but because he didn't know neither did she and a major problem was that he couldn't talk about any problems or if she was angry with him he'd just seize up and couldn't talk. He says she was very controlling and when he found it hard to talk shed shout at him and was very unreasonable. in the end he just cut contact one day without even finishing things properly, he just did it over the phone during an argument and they never spoke after that. he wrote her a letter a couple of months after explaining that he was sorry and he couldn't be with her and he was ill ect but she never even acknowledged shed received the letter which i think he found very hard.
he is very low and quite often can't even cuddle me as he says he just finds it hard to love but he does love me a lot and says that I'm so different to his ex because i really care for him, which i do. He has nightmares a lot and they are about her, about the break up and he feels horrendous pain specifcally the pain of losing someone. about three months into the relationship i saw that one of the last searches on his Facebook was her, whom he's not friends with anymore and i was very upset and felt betrayed. he explained that its not because he wants to be with her its just a lot of his depression stems from that relationship and he doesn't know why he dose it. anyway he promised he wouldn't do it again, i asked him a few weeks ago if he had done it again and he promised me he hadn't. Then he was out a few days later and i was on his i pad and tapped on the search bar and her name was one of the most searched names on his Facebook.
When he got home i asked him about it and he just seized up and couldn't talk to me. i asked him if he wished it had worked out with her and if wants her back to which he replied "no because she's not good for me and theres a reason i finished with her". i asked why is he looking and he said he feels like he's looking for an answer to the pain he feels but says he really loves me and wants us to be together but its hard for him to love sometimes, which i understand as my dad was depressed for five years. He's promised me he won't look again and has deleted his Facebook so he won't be reminded of her as it causes him to think of painful things. I don't know if he just feels guilty about the way he ended it or because he wishes he'd been able to save the relationship. she has a boyfriend now and would never get back with my boyfriend and I'm worried because he know that he's telling me he doesn't want to be with her. I don't want him to be with me just because he's trying cure the pain of losing her and doesn't want to be on his own.
I respect his privacy and he respects mine but I'm starting to feel like i can't trust him after he's lied to me and to protect myself to get the truth i feel i need to check up on him which i don't want to do. i love him so the depression is something i can deal with as iv lived wth someone that has it so I'm aware but i don't want to be second best and just a comfort for him. I don't want to get hurt is my main problem but i don't know if he's being truthful or if he even knows what he feels. I do everything i can for him to try and help ease the pain, looking for psychotherapists or talking through things, but I'm also in the last year of a degree as a mature student and its tough. i just don't want to be taken for granted if its not me he really wants.

has been in his situation and can help me understand?